In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image and performing some operations can cause slab-out-of-bounds write access in __btrfs_map_block in fs/btrfs/volumes.c, because a value of 1 for the number of data stripes is mishandled.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image and performing some operations can     cause slab-out-of-bounds write access in __btrfs_map_block in fs/btrfs/volumes.c, because a value of 1 for     the number of data stripes is mishandled. (CVE-2019-19816)

Note that Nessus relies on the presence of the package as reported by the vendor.

Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service or information leaks.

CVE-2019-19318, CVE-2019-19813, CVE-2019-19816

'Team bobfuzzer' reported bugs in Btrfs that could lead to a use-after-free or heap buffer overflow, and could be triggered by crafted filesystem images. A user permitted to mount and access arbitrary filesystems could use these to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-27815

A flaw was reported in the JFS filesystem code allowing a local attacker with the ability to set extended attributes to cause a denial of service.

CVE-2020-27825

Adam 'pi3' Zabrocki reported a use-after-free flaw in the ftrace ring buffer resizing logic due to a race condition, which could result in denial of service or information leak.

CVE-2020-28374

David Disseldorp discovered that the LIO SCSI target implementation performed insufficient checking in certain XCOPY requests. An attacker with access to a LUN and knowledge of Unit Serial Number assignments can take advantage of this flaw to read and write to any LIO backstore, regardless of the SCSI transport settings.

CVE-2020-29568 (XSA-349)

Michael Kurth and Pawel Wieczorkiewicz reported that frontends can trigger OOM in backends by updating a watched path.

CVE-2020-29569 (XSA-350)

Olivier Benjamin and Pawel Wieczorkiewicz reported a use-after-free flaw which can be triggered by a block frontend in Linux blkback. A misbehaving guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend.

CVE-2020-29660

Jann Horn reported a locking inconsistency issue in the tty subsystem which may allow a local attacker to mount a read-after-free attack against TIOCGSID.

CVE-2020-29661

Jann Horn reported a locking issue in the tty subsystem which can result in a use-after-free. A local attacker can take advantage of this flaw for memory corruption or privilege escalation.

CVE-2020-36158

A buffer overflow flaw was discovered in the mwifiex WiFi driver which could result in denial of service or the execution of arbitrary code via a long SSID value.

CVE-2021-3178

&#x5434;&#x5F02; reported an information leak in the NFSv3 server.
When only a subdirectory of a filesystem volume is exported, an NFS client listing the exported directory would obtain a file handle to the parent directory, allowing it to access files that were not meant to be exported.

Even after this update, it is still possible for NFSv3 clients to guess valid file handles and access files outside an exported subdirectory, unless the 'subtree_check' export option is enabled. It is recommended that you do not use that option but only export whole filesystem volumes.

CVE-2021-3347

It was discovered that PI futexes have a kernel stack use-after-free during fault handling. An unprivileged user could use this flaw to crash the kernel (resulting in denial of service) or for privilege escalation.

CVE-2021-26930 (XSA-365)

Olivier Benjamin, Norbert Manthey, Martin Mazein, and Jan H.
Sch&ouml;nherr discovered that the Xen block backend driver (xen-blkback) did not handle grant mapping errors correctly. A malicious guest could exploit this bug to cause a denial of service (crash), or possibly an information leak or privilege escalation, within the domain running the backend, which is typically dom0.

CVE-2021-26931 (XSA-362), CVE-2021-26932 (XSA-361), CVE-2021-28038 (XSA-367)

Jan Beulich discovered that the Xen support code and various Xen backend drivers did not handle grant mapping errors correctly. A malicious guest could exploit these bugs to cause a denial of service (crash) within the domain running the backend, which is typically dom0.

CVE-2021-27363

Adam Nichols reported that the iSCSI initiator subsystem did not properly restrict access to transport handle attributes in sysfs. On a system acting as an iSCSI initiator, this is an information leak to local users and makes it easier to exploit CVE-2021-27364.

CVE-2021-27364

Adam Nichols reported that the iSCSI initiator subsystem did not properly restrict access to its netlink management interface. On a system acting as an iSCSI initiator, a local user could use these to cause a denial of service (disconnection of storage) or possibly for privilege escalation.

CVE-2021-27365

Adam Nichols reported that the iSCSI initiator subsystem did not correctly limit the lengths of parameters or 'passthrough PDUs' sent through its netlink management interface. On a system acting as an iSCSI initiator, a local user could use these to leak the contents of kernel memory, to cause a denial of service (kernel memory corruption or crash), and probably for privilege escalation.

For Debian 9 stretch, these problems have been fixed in version 4.9.258-1.

We recommend that you upgrade your linux packages.

For the detailed security status of linux please refer to its security tracker page at: https://security-tracker.debian.org/tracker/linux

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The remote Ubuntu 16.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4709-1 advisory.

    It was discovered that the LIO SCSI target implementation in the Linux kernel performed insufficient     identifier checking in certain XCOPY requests. An attacker with access to at least one LUN in a multiple     backstore environment could use this to expose sensitive information or modify data. (CVE-2020-28374)

    Wen Xu discovered that the XFS filesystem implementation in the Linux kernel did not properly track inode     validations. An attacker could use this to construct a malicious XFS image that, when mounted, could cause     a denial of service (system crash). (CVE-2018-13093)

    It was discovered that the btrfs file system implementation in the Linux kernel did not properly validate     file system metadata in some situations. An attacker could use this to construct a malicious btrfs image     that, when mounted, could cause a denial of service (system crash). (CVE-2019-19813, CVE-2019-19816)

    Bodong Zhao discovered a use-after-free in the Sun keyboard driver implementation in the Linux kernel. A     local attacker could use this to cause a denial of service or possibly execute arbitrary code.
    (CVE-2020-25669)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Ubuntu 16.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4708-1 advisory.

    Wen Xu discovered that the XFS filesystem implementation in the Linux kernel did not properly track inode     validations. An attacker could use this to construct a malicious XFS image that, when mounted, could cause     a denial of service (system crash). (CVE-2018-13093)

    It was discovered that the btrfs file system implementation in the Linux kernel did not properly validate     file system metadata in some situations. An attacker could use this to construct a malicious btrfs image     that, when mounted, could cause a denial of service (system crash). (CVE-2019-19813, CVE-2019-19816)

    Bodong Zhao discovered a use-after-free in the Sun keyboard driver implementation in the Linux kernel. A     local attacker could use this to cause a denial of service or possibly execute arbitrary code.
    (CVE-2020-25669)

    Daniel Axtens discovered that PowerPC RTAS implementation in the Linux kernel did not properly restrict     memory accesses in some situations. A privileged local attacker could use this to arbitrarily modify     kernel memory, potentially bypassing kernel lockdown restrictions. (CVE-2020-27777)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of kernel installed on the remote host is prior to 4.14.214-118.339. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS-2021-1477 advisory.

    In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image, performing some operations, and     then making a syncfs system call can lead to a use-after-free in __mutex_lock in kernel/locking/mutex.c.
    This is related to mutex_can_spin_on_owner in kernel/locking/mutex.c, __btrfs_qgroup_free_meta in     fs/btrfs/qgroup.c, and btrfs_insert_delayed_items in fs/btrfs/delayed-inode.c. (CVE-2019-19813)

    A flaw was found in the implementation of the BTRFS file system code in the Linux kernel. An attacker, who     is able to mount a crafted BTRFS filesystem and perform common filesystem operations, can possibly cause     an out-of-bounds write to memory. This could lead to memory corruption or privilege escalation.
    (CVE-2019-19816)

    Array index out of bounds access when setting extended attributes on journaling filesystems.
    (CVE-2020-27815)

    An issue was discovered in Xen through 4.14.x. Some OSes (such as Linux, FreeBSD, and NetBSD) are     processing watch events using a single thread. If the events are received faster than the thread is able     to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OOM in the     backend. All systems with a FreeBSD, Linux, or NetBSD (any version) dom0 are vulnerable. (CVE-2020-29568)

    An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux     kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped.
    However, the handler may not have time to run if the frontend quickly toggles between the states connect     and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving     guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege     escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.
    (CVE-2020-29569)

    A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13.
    drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c may allow a read-after-free attack against TIOCGSID,     aka CID-c8bcd9c5be24. (CVE-2020-29660)

    A locking vulnerability was found in the tty subsystem of the Linux kernel in drivers/tty/tty_jobctrl.c.
    This flaw allows a local attacker to possibly corrupt memory or escalate privileges. The highest threat     from this vulnerability is to confidentiality, integrity, as well as system availability. (CVE-2020-29661)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The version of kernel installed on the remote host is prior to 4.14.214-160.339. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2-2021-1588 advisory.

    In the Linux kernel 5.0.21, mounting a crafted btrfs filesystem image, performing some operations, and     then making a syncfs system call can lead to a use-after-free in __mutex_lock in kernel/locking/mutex.c.
    This is related to mutex_can_spin_on_owner in kernel/locking/mutex.c, __btrfs_qgroup_free_meta in     fs/btrfs/qgroup.c, and btrfs_insert_delayed_items in fs/btrfs/delayed-inode.c. (CVE-2019-19813)

    A flaw was found in the implementation of the BTRFS file system code in the Linux kernel. An attacker, who     is able to mount a crafted BTRFS filesystem and perform common filesystem operations, can possibly cause     an out-of-bounds write to memory. This could lead to memory corruption or privilege escalation.
    (CVE-2019-19816)

    This flaw is rated as having Moderate impact, there is a possibility that there is a write, although it is     an uncontrolled write in a fixed offset from the current location. Also this issue is in non-default     filesystem. (CVE-2020-27815)

    An issue was discovered in Xen through 4.14.x. Some OSes (such as Linux, FreeBSD, and NetBSD) are     processing watch events using a single thread. If the events are received faster than the thread is able     to handle, they will get queued. As the queue is unbounded, a guest may be able to trigger an OOM in the     backend. All systems with a FreeBSD, Linux, or NetBSD (any version) dom0 are vulnerable. (cve-2020-29568)

    An issue was discovered in the Linux kernel through 5.10.1, as used with Xen through 4.14.x. The Linux     kernel PV block backend expects the kernel thread handler to reset ring->xenblkd to NULL when stopped.
    However, the handler may not have time to run if the frontend quickly toggles between the states connect     and disconnect. As a consequence, the block backend may re-use a pointer after it was freed. A misbehaving     guest can trigger a dom0 crash by continuously connecting / disconnecting a block frontend. Privilege     escalation and information leaks cannot be ruled out. This only affects systems with a Linux blkback.
    (cve-2020-29569)

    A locking inconsistency issue was discovered in the tty subsystem of the Linux kernel through 5.9.13.
    drivers/tty/tty_io.c and drivers/tty/tty_jobctrl.c may allow a read-after-free attack against TIOCGSID,     aka CID-c8bcd9c5be24. (CVE-2020-29660)

    A locking vulnerability was found in the tty subsystem of the Linux kernel in drivers/tty/tty_jobctrl.c.
    This flaw allows a local attacker to possibly corrupt memory or escalate privileges. The highest threat     from this vulnerability is to confidentiality, integrity, as well as system availability. (CVE-2020-29661)

Tenable has extracted the preceding description block directly from the tested product security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote Oracle Linux 7 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2020-5995 advisory.

    - vt: Disable KD_FONT_OP_COPY (Daniel Vetter)  [Orabug: 32187748]  {CVE-2020-28974}
    - xen/events: block rogue events for some time (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/events: defer eoi in case of excessive number of events (Juergen Gross)  [Orabug: 32177538]     {CVE-2020-27673}
    - xen/events: use a common cpu hotplug hook for event channels (Juergen Gross)  [Orabug: 32177538]     {CVE-2020-27673}
    - xen/events: switch user event channels to lateeoi model (Juergen Gross)  [Orabug: 32177538]     {CVE-2020-27673}
    - xen/pciback: use lateeoi irq binding (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/pvcallsback: use lateeoi irq binding (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/scsiback: use lateeoi irq binding (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/netback: use lateeoi irq binding (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/blkback: use lateeoi irq binding (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/events: add a new 'late EOI' evtchn framework (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/events: fix race in evtchn_fifo_unmask() (Juergen Gross)  [Orabug: 32177538]  {CVE-2020-27673}
    - xen/events: add a proper barrier to 2-level uevent unmasking (Juergen Gross)  [Orabug: 32177538]     {CVE-2020-27673}
    - tty: make FONTX ioctl use the tty pointer they were actually passed (Linus Torvalds)  [Orabug: 32122729]     {CVE-2020-25668}
    - vt: keyboard, extend func_buf_lock to readers (Jiri Slaby)  [Orabug: 32122952]  {CVE-2020-25656}     {CVE-2020-25656}
    - vt: keyboard, simplify vt_kdgkbsent (Jiri Slaby)  [Orabug: 32122952]  {CVE-2020-25656}
    - perf/core: Fix a memory leak in perf_event_parse_addr_filter() (kiyin)  [Orabug: 32131175]     {CVE-2020-25704}
    - perf/core: Fix bad use of igrab() (Song Liu)  [Orabug: 32131175]  {CVE-2020-25704}
    - powercap: restrict energy meter to root access (Kanth Ghatraju)  [Orabug: 32138487]  {CVE-2020-8694}     {CVE-2020-8695}
    - btrfs: inode: Verify inode mode to avoid NULL pointer dereference (Qu Wenruo)  [Orabug: 31864726]     {CVE-2019-19816}
    - Bluetooth: A2MP: Fix not initializing all members (Luiz Augusto von Dentz)  [Orabug: 32021288]     {CVE-2020-12352}

Tenable has extracted the preceding description block directly from the Oracle Linux security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

Several vulnerabilities have been discovered in the Linux kernel that may lead to the execution of arbitrary code, privilege escalation, denial of service or information leaks.

CVE-2019-19039

'Team bobfuzzer' reported a bug in Btrfs that could lead to an assertion failure (WARN). A user permitted to mount and access arbitrary filesystems could use this to cause a denial of service (crash) if the panic_on_warn kernel parameter is set.

CVE-2019-19377

'Team bobfuzzer' reported a bug in Btrfs that could lead to a use-after-free. A user permitted to mount and access arbitrary filesystems could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2019-19770

The syzbot tool discovered a race condition in the block I/O tracer (blktrace) that could lead to a system crash. Since blktrace can only be controlled by privileged users, the security impact of this is unclear.

CVE-2019-19816

'Team bobfuzzer' reported a bug in Btrfs that could lead to an out-of-bounds write. A user permitted to mount and access arbitrary filesystems could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-0423

A race condition was discovered in the Android binder driver, that could result in a use-after-free. On systems using this driver, a local user could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-8694

Multiple researchers discovered that the powercap subsystem allowed all users to read CPU energy meters, by default. On systems using Intel CPUs, this provided a side channel that could leak sensitive information between user processes, or from the kernel to user processes. The energy meters are now readable only by root, by default.

This issue can be mitigated by running :

chmod go-r /sys/devices/virtual/powercap/*/*/energy_uj

This needs to be repeated each time the system is booted with an unfixed kernel version.

CVE-2020-14351

A race condition was discovered in the performance events subsystem, which could lead to a use-after-free. A local user permitted to access performance events could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

Debian's kernel configuration does not allow unprivileged users to access peformance events by default, which fully mitigates this issue.

CVE-2020-25656

Yuan Ming and Bodong Zhao discovered a race condition in the virtual terminal (vt) driver that could lead to a use-after-free. A local user with the CAP_SYS_TTY_CONFIG capability could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-25668

Yuan Ming and Bodong Zhao discovered a race condition in the virtual terminal (vt) driver that could lead to a use-after-free. A local user with access to a virtual terminal, or with the CAP_SYS_TTY_CONFIG capability, could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-25669

Bodong Zhao discovered a bug in the Sun keyboard driver (sunkbd) that could lead to a use-after-free. On a system using this driver, a local user could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-25704

kiyin(&#x5C39;&#x4EAE;) discovered a potential memory leak in the performance events subsystem. A local user permitted to access performance events could use this to cause a denial of service (memory exhaustion).

Debian's kernel configuration does not allow unprivileged users to access peformance events by default, which fully mitigates this issue.

CVE-2020-25705

Keyu Man reported that strict rate-limiting of ICMP packet transmission provided a side-channel that could help networked attackers to carry out packet spoofing. In particular, this made it practical for off-path networked attackers to 'poison' DNS caches with spoofed responses ('SAD DNS' attack).

This issue has been mitigated by randomising whether packets are counted against the rate limit.

CVE-2020-27673 / XSA-332

Julien Grall from Arm discovered a bug in the Xen event handling code.
Where Linux was used in a Xen dom0, unprivileged (domU) guests could cause a denial of service (excessive CPU usage or hang) in dom0.

CVE-2020-27675 / XSA-331

Jinoh Kang of Theori discovered a race condition in the Xen event handling code. Where Linux was used in a Xen dom0, unprivileged (domU) guests could cause a denial of service (crash) in dom0.

CVE-2020-28941

Shisong Qin and Bodong Zhao discovered a bug in the Speakup screen reader subsystem. Speakup assumed that it would only be bound to one terminal (tty) device at a time, but did not enforce this. A local user could exploit this bug to cause a denial of service (crash or memory exhaustion).

CVE-2020-28974

Yuan Ming discovered a bug in the virtual terminal (vt) driver that could lead to an out-of-bounds read. A local user with access to a virtual terminal, or with the CAP_SYS_TTY_CONFIG capability, could possibly use this to obtain sensitive information from the kernel or to cause a denial of service (crash).

The specific ioctl operation affected by this bug (KD_FONT_OP_COPY) has been disabled, as it is not believed that any programs depended on it.

For Debian 9 stretch, these problems have been fixed in version 4.19.160-2~deb9u1.

We recommend that you upgrade your linux-4.19 packages.

For the detailed security status of linux-4.19 please refer to its security tracker page at:
https://security-tracker.debian.org/tracker/linux-4.19

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

An update of the linux package has been released.

Several vulnerabilities have been discovered in the Linux kernel that may lead to a privilege escalation, denial of service, or information leak.

CVE-2019-3874

Kernel buffers allocated by the SCTP network protocol were not limited by the memory cgroup controller. A local user could potentially use this to evade container memory limits and to cause a denial of service (excessive memory use).

CVE-2019-19448, CVE-2019-19813, CVE-2019-19816

'Team bobfuzzer' reported bugs in Btrfs that could lead to a use-after-free or heap buffer overflow, and could be triggered by crafted filesystem images. A user permitted to mount and access arbitrary filesystems could use these to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-10781

Luca Bruno of Red Hat discovered that the zram control file /sys/class/zram-control/hot_add was readable by all users. On a system with zram enabled, a local user could use this to cause a denial of service (memory exhaustion).

CVE-2020-12888

It was discovered that the PCIe Virtual Function I/O (vfio-pci) driver allowed users to disable a device's memory space while it was still mapped into a process. On some hardware platforms, local users or guest virtual machines permitted to access PCIe Virtual Functions could use this to cause a denial of service (hardware error and crash).

CVE-2020-14314

A bug was discovered in the ext4 filesystem that could lead to an out-of-bound read. A local user permitted to mount and access arbitrary filesystem images could use this to cause a denial of service (crash).

CVE-2020-14331

A bug was discovered in the VGA console driver's soft-scrollback feature that could lead to a heap buffer overflow. On a system with a custom kernel that has CONFIG_VGACON_SOFT_SCROLLBACK enabled, a local user with access to a console could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-14356

A bug was discovered in the cgroup subsystem's handling of socket references to cgroups. In some cgroup configurations, this could lead to a use-after-free. A local user might be able to use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-14385

A bug was discovered in XFS, which could lead to an extended attribute (xattr) wrongly being detected as invalid. A local user with access to an XFS filesystem could use this to cause a denial of service (filesystem shutdown).

CVE-2020-14386

Or Cohen discovered a bug in the packet socket (AF_PACKET) implementation which could lead to a heap buffer overflow. A local user with the CAP_NET_RAW capability (in any user namespace) could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

CVE-2020-14390

Minh Yuan discovered a bug in the framebuffer console driver's scrollback feature that could lead to a heap buffer overflow. On a system using framebuffer consoles, a local user with access to a console could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation.

The scrollback feature has been disabled for now, as no other fix was available for this issue.

CVE-2020-16166

Amit Klein reported that the random number generator used by the network stack might not be re-seeded for long periods of time, making e.g. client port number allocations more predictable. This made it easier for remote attackers to carry out some network- based attacks such as DNS cache poisoning or device tracking.

CVE-2020-25212

A bug was discovered in the NFSv4 client implementation that could lead to a heap buffer overflow. A malicious NFS server could use this to cause a denial of service (crash or memory corruption) or possibly to execute arbitrary code on the client.

CVE-2020-25284

It was discovered that the Rados block device (rbd) driver allowed tasks running as uid 0 to add and remove rbd devices, even if they dropped capabilities. On a system with the rbd driver loaded, this might allow privilege escalation from a container with a task running as root.

CVE-2020-25285

A race condition was discovered in the hugetlb filesystem's sysctl handlers, that could lead to stack corruption. A local user permitted to write to hugepages sysctls could use this to cause a denial of service (crash or memory corruption) or possibly for privilege escalation. By default only the root user can do this.

CVE-2020-25641

The syzbot tool found a bug in the block layer that could lead to an infinite loop. A local user with access to a raw block device could use this to cause a denial of service (unbounded CPU use and possible system hang).

CVE-2020-26088

It was discovered that the NFC (Near Field Communication) socket implementation allowed any user to create raw sockets. On a system with an NFC interface, this allowed local users to evade local network security policy.

For Debian 9 stretch, these problems have been fixed in version 4.19.146-1~deb9u1. This update additionally fixes Debian bugs #966846, #966917, and #968567; and includes many more bug fixes from stable updates 4.19.133-4.19.146 inclusive.

We recommend that you upgrade your linux-4.19 packages.

For the detailed security status of linux-4.19 please refer to its security tracker page at:
https://security-tracker.debian.org/tracker/linux-4.19

NOTE: Tenable Network Security has extracted the preceding description block directly from the DLA security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

The remote Ubuntu 16.04 LTS / 18.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4414-1 advisory.

    It was discovered that the network block device (nbd) implementation in the Linux kernel did not properly     check for error conditions in some situations. An attacker could possibly use this to cause a denial of     service (system crash). (CVE-2019-16089)

    It was discovered that the btrfs file system implementation in the Linux kernel did not properly validate     file system metadata in some situations. An attacker could use this to construct a malicious btrfs image     that, when mounted, could cause a denial of service (system crash). (CVE-2019-19036, CVE-2019-19318,     CVE-2019-19813, CVE-2019-19816)

    It was discovered that the btrfs implementation in the Linux kernel did not properly detect that a block     was marked dirty in some situations. An attacker could use this to specially craft a file system image     that, when unmounted, could cause a denial of service (system crash). (CVE-2019-19377)

    It was discovered that the kernel->user space relay implementation in the Linux kernel did not properly     check return values in some situations. A local attacker could possibly use this to cause a denial of     service (system crash). (CVE-2019-19462)

    Matthew Sheets discovered that the SELinux network label handling implementation in the Linux kernel could     be coerced into de-referencing a NULL pointer. A remote attacker could use this to cause a denial of     service (system crash). (CVE-2020-10711)

    It was discovered that the SCSI generic (sg) driver in the Linux kernel did not properly handle certain     error conditions correctly. A local privileged attacker could use this to cause a denial of service     (system crash). (CVE-2020-12770)

    It was discovered that the USB Gadget device driver in the Linux kernel did not validate arguments passed     from configfs in some situations. A local attacker could possibly use this to cause a denial of service     (system crash) or possibly expose sensitive information. (CVE-2020-13143)

    It was discovered that the efi subsystem in the Linux kernel did not handle memory allocation failures     during early boot in some situations. A local attacker could possibly use this to cause a denial of     service (system crash). (CVE-2019-12380)

    It was discovered that the btrfs file system in the Linux kernel in some error conditions could report     register information to the dmesg buffer. A local attacker could possibly use this to expose sensitive     information. (CVE-2019-19039)

Tenable has extracted the preceding description block directly from the Ubuntu security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
222835	Linux Distros Unpatched Vulnerability : CVE-2019-19816	Nessus	Misc.	high
147532	Debian DLA-2586-1 : linux security update	Nessus	Debian Local Security Checks	high
145516	Ubuntu 16.04 LTS : Linux kernel vulnerabilities (USN-4709-1)	Nessus	Ubuntu Local Security Checks	high
145510	Ubuntu 16.04 LTS : Linux kernel vulnerabilities (USN-4708-1)	Nessus	Ubuntu Local Security Checks	high
145458	Amazon Linux AMI : kernel (ALAS-2021-1477)	Nessus	Amazon Linux Local Security Checks	high
145456	Amazon Linux 2 : kernel (ALAS-2021-1588)	Nessus	Amazon Linux Local Security Checks	high
144207	Oracle Linux 7 : Unbreakable Enterprise kernel (ELSA-2020-5995)	Nessus	Oracle Linux Local Security Checks	high
144097	Debian DLA-2483-1 : linux-4.19 security update	Nessus	Debian Local Security Checks	high
141098	Photon OS 2.0: Linux PHSA-2020-2.0-0287	Nessus	PhotonOS Local Security Checks	high
141094	Photon OS 3.0: Linux PHSA-2020-3.0-0145	Nessus	PhotonOS Local Security Checks	high
141091	Photon OS 1.0: Linux PHSA-2020-1.0-0329	Nessus	PhotonOS Local Security Checks	high
140933	Debian DLA-2385-1 : linux-4.19 security update	Nessus	Debian Local Security Checks	high
138139	Ubuntu 16.04 LTS / 18.04 LTS : Linux kernel vulnerabilities (USN-4414-1)	Nessus	Ubuntu Local Security Checks	high

Detections

Analytics

CVE-2019-19816

high

Tenable Plugins

high

high

high

high

high

high

high

high

high

high

high

high

high