SynopsisThe remote EulerOS host is missing multiple security updates.
DescriptionAccording to the versions of the kernel packages installed, the EulerOS installation on the remote host is affected by the following vulnerabilities :
- An integer overflow flaw was found in the way the Linux kernel's networking subsystem processed TCP Selective Acknowledgment (SACK) segments. While processing SACK segments, the Linux kernel's socket buffer (SKB) data structure becomes fragmented. Each fragment is about TCP maximum segment size (MSS) bytes. To efficiently process SACK blocks, the Linux kernel merges multiple fragmented SKBs into one, potentially overflowing the variable holding the number of segments. A remote attacker could use this flaw to crash the Linux kernel by sending a crafted sequence of SACK segments on a TCP connection with small value of TCP MSS, resulting in a denial of service (DoS). (CVE-2019-11477)
- Kernel: tcp: excessive resource consumption while processing SACK blocks allows remote denial of service (CVE-2019-11478)
- Kernel: tcp: excessive resource consumption for TCP connections with low MSS allows remote denial of service (CVE-2019-11479)
- The Linux kernel is vulnerable to an out-of-bounds read in ext4/balloc.c:ext4_valid_block_bitmap() function. An attacker could trick a legitimate user or a privileged attacker could exploit this by mounting a crafted ext4 image to cause a crash.(CVE-2018-1093)
- The Siemens R3964 line discipline driver in drivers/tty/n_r3964.c in the Linux kernel before 5.0.8 has multiple race conditions.(CVE-2019-11486)
- A flaw was found in the Linux kernel where the coredump implementation does not use locking or other mechanisms to prevent vma layout or vma flags changes while it runs. This allows local users to obtain sensitive information, cause a denial of service (DoS), or possibly have unspecified other impact by triggering a race condition with mmget_not_zero or get_task_mm calls.(CVE-2019-11599)
- A race condition in perf_event_open() allows local attackers to leak sensitive data from setuid programs.
As no relevant locks (in particular the cred_guard_mutex) are held during the ptrace_may_access() call, it is possible for the specified target task to perform an execve() syscall with setuid execution before perf_event_alloc() actually attaches to it, allowing an attacker to bypass the ptrace_may_access() check and the perf_event_exit_task(current) call that is performed in install_exec_creds() during privileged execve() calls.(CVE-2019-3901)
- In the tun subsystem in the Linux kernel before 4.13.14, dev_get_valid_name is not called before register_netdevice. This allows local users to cause a denial of service (NULL pointer dereference and panic) via an ioctl(TUNSETIFF) call with a dev name containing a / character. This is similar to CVE-2013-4343.(CVE-2018-7191)
- An issue was discovered in the Linux kernel before 4.20. There is a race condition in smp_task_timedout() and smp_task_done() in drivers/scsi/libsas/sas_expander.c, leading to a use-after-free.(CVE-2018-20836)
- A flaw was found in the Linux kernel, prior to version 5.0.7, in drivers/scsi/megaraid/megaraid_sas_base.c, where a NULL pointer dereference can occur when megasas_create_frame_pool() fails in megasas_alloc_cmds(). An attacker can crash the system if they were able to load the megaraid_sas kernel module and groom memory beforehand, leading to a denial of service (DoS), related to a use-after-free.(CVE-2019-11810)
Note that Tenable Network Security has extracted the preceding description block directly from the EulerOS security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
SolutionUpdate the affected kernel packages.