An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It ignores the top byte in the address passed to the brk system call, potentially moving the memory break downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to cause heap corruption with the GNU C Library malloc implementation.

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-004716 advisory.

    An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It     ignores the top byte in the address passed to the brk system call, potentially moving the memory break     downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to     cause heap corruption with the GNU C Library malloc implementation.

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

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

The Unity Linux 20 host has a package installed that is affected by a vulnerability as referenced in the UTSA-2026-004107 advisory.

    An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It     ignores the top byte in the address passed to the brk system call, potentially moving the memory break     downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to     cause heap corruption with the GNU C Library malloc implementation.

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

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

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

  - An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It     ignores the top byte in the address passed to the brk system call, potentially moving the memory break     downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to     cause heap corruption with the GNU C Library malloc implementation. (CVE-2020-9391)

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

The version of kernel installed on the remote host is prior to 5.4.38-17.76. It is, therefore, affected by multiple vulnerabilities as referenced in the ALAS2KERNEL-5.4-2022-011 advisory.

    In the Linux kernel 5.3.10, there is a use-after-free (read) in the perf_trace_lock_acquire function     (related to include/trace/events/lock.h). (CVE-2019-19769)

    A NULL pointer dereference flaw was found in the Linux kernel's SELinux subsystem. This flaw occurs while     importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible     bitmap via the' ebitmap_netlbl_import' routine. While processing the CIPSO restricted bitmap tag in the     'cipso_v4_parsetag_rbm' routine, it sets the security attribute to indicate that the category bitmap is     present, even if it has not been allocated. This issue leads to a NULL pointer dereference issue while     importing the same category bitmap into SELinux. This flaw allows a remote network user to crash the     system kernel, resulting in a denial of service. (CVE-2020-10711)

    A Use After Free vulnerability in Fedora Linux kernel 5.9.0-rc9 allows attackers to obatin sensitive     information via vgacon_invert_region() function. (CVE-2020-27418)

    In the Linux kernel, the following vulnerability has been resolved:

    net_sched: keep alloc_hash updated after hash allocation (CVE-2020-36791)

    An issue was discovered in the Linux kernel 5.4 and 5.5 through 5.5.6 on the AArch64 architecture. It     ignores the top byte in the address passed to the brk system call, potentially moving the memory break     downwards when the application expects it to move upwards, aka CID-dcde237319e6. This has been observed to     cause heap corruption with the GNU C Library malloc implementation. (CVE-2020-9391)

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 / 8 host has packages installed that are affected by multiple vulnerabilities as referenced in the ELSA-2020-5691 advisory.

    [5.4.17-2011.2.2uek]
    - scsi: qla2xxx: Move free of fcport out of interrupt context (Joe Carnuccio)  [Orabug: 31225231]
    - xfs: move inode flush to the sync workqueue (Darrick J. Wong)  [Orabug: 31132665]
    - arm64: Kconfig: Enable NODES_SPAN_OTHER_NODES config for NUMA (Hoan Tran)  [Orabug: 31049202]
    - scsi: bnx2fc: timeout calculation invalid for bnx2fc_eh_abort() (Laurence Oberman)  [Orabug: 31207643]
    - jbd2: disable CONFIG_JBD2_DEBUG (Junxiao Bi)  [Orabug: 31264694]

    [5.4.17-2011.2.1uek]
    - x86/mce: Restart the system when LMCE UE error occurs (Thomas Tai)  [Orabug: 31218859]

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.

The 5.5.6 stable kernel update contains a number of important fixes across the tree.

Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website.
Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

ID	Name	Product	Family	Severity
290191	Unity Linux 20.1060e / 20.1070e Security Update: kernel (UTSA-2026-004716)	Nessus	Unity Linux Local Security Checks	medium
288414	Unity Linux 20.1060a / 20.1070a Security Update: kernel (UTSA-2026-004107)	Nessus	Unity Linux Local Security Checks	medium
244011	Linux Distros Unpatched Vulnerability : CVE-2020-9391	Nessus	Misc.	medium
160458	Amazon Linux 2 : kernel (ALASKERNEL-5.4-2022-011)	Nessus	Amazon Linux Local Security Checks	high
136727	Oracle Linux 7 / 8 : Unbreakable Enterprise kernel (ELSA-2020-5691)	Nessus	Oracle Linux Local Security Checks	high
134187	Fedora 31 : kernel / kernel-headers / kernel-tools (2020-3cd64d683c)	Nessus	Fedora Local Security Checks	medium

Detections

Analytics

CVE-2020-9391

medium

Tenable Plugins

medium

medium

medium

high

high

medium