An issue was discovered in mm/mmap.c in the Linux kernel before 5.7.11. There is a race condition between certain expand functions (expand_downwards and expand_upwards) and page-table free operations from an munmap call, aka CID-246c320a8cfe.

The remote Ubuntu 20.04 LTS host has a package installed that is affected by multiple vulnerabilities as referenced in the USN-4752-1 advisory.

    Daniele Antonioli, Nils Ole Tippenhauer, and Kasper Rasmussen discovered that legacy pairing and secure-     connections pairing authentication in the Bluetooth protocol could allow an unauthenticated user to     complete authentication without pairing credentials via adjacent access. A physically proximate attacker     could use this to impersonate a previously paired Bluetooth device. (CVE-2020-10135)

    Jay Shin discovered that the ext4 file system implementation in the Linux kernel did not properly handle     directory access with broken indexing, leading to an out-of-bounds read vulnerability. A local attacker     could use this to cause a denial of service (system crash). (CVE-2020-14314)

    It was discovered that the block layer implementation in the Linux kernel did not properly perform     reference counting in some situations, leading to a use-after-free vulnerability. A local attacker could     use this to cause a denial of service (system crash). (CVE-2020-15436)

    It was discovered that the serial port driver in the Linux kernel did not properly initialize a pointer in     some situations. A local attacker could possibly use this to cause a denial of service (system crash).
    (CVE-2020-15437)

    Andy Nguyen discovered that the Bluetooth HCI event packet parser in the Linux kernel did not properly     handle event advertisements of certain sizes, leading to a heap-based buffer overflow. A physically     proximate remote attacker could use this to cause a denial of service (system crash) or possibly execute     arbitrary code. (CVE-2020-24490)

    It was discovered that the NFS client implementation in the Linux kernel did not properly perform bounds     checking before copying security labels in some situations. A local attacker could use this to cause a     denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-25212)

    It was discovered that the Rados block device (rbd) driver in the Linux kernel did not properly perform     privilege checks for access to rbd devices in some situations. A local attacker could use this to map or     unmap rbd block devices. (CVE-2020-25284)

    It was discovered that the block layer subsystem in the Linux kernel did not properly handle zero-length     requests. A local attacker could use this to cause a denial of service. (CVE-2020-25641)

    It was discovered that the HDLC PPP implementation in the Linux kernel did not properly validate input in     some situations. A local attacker could use this to cause a denial of service (system crash) or possibly     execute arbitrary code. (CVE-2020-25643)

    Kiyin () discovered that the perf subsystem in the Linux kernel did not properly deallocate memory     in some situations. A privileged attacker could use this to cause a denial of service (kernel memory     exhaustion). (CVE-2020-25704)

    It was discovered that the KVM hypervisor in the Linux kernel did not properly handle interrupts in     certain situations. A local attacker in a guest VM could possibly use this to cause a denial of service     (host system crash). (CVE-2020-27152)

    It was discovered that the jfs file system implementation in the Linux kernel contained an out-of-bounds     read vulnerability. A local attacker could use this to possibly cause a denial of service (system crash).
    (CVE-2020-27815)

    It was discovered that an information leak existed in the syscall implementation in the Linux kernel on 32     bit systems. A local attacker could use this to expose sensitive information (kernel memory).
    (CVE-2020-28588)

    It was discovered that the framebuffer implementation in the Linux kernel did not properly perform range     checks in certain situations. A local attacker could use this to expose sensitive information (kernel     memory). (CVE-2020-28915)

    Jann Horn discovered a race condition in the copy-on-write implementation in the Linux kernel when     handling hugepages. A local attacker could use this to gain unintended write access to read-only memory     pages. (CVE-2020-29368)

    Jann Horn discovered that the mmap implementation in the Linux kernel contained a race condition when     handling munmap() operations, leading to a read-after-free vulnerability. A local attacker could use this     to cause a denial of service (system crash) or possibly expose sensitive information. (CVE-2020-29369)

    Jann Horn discovered that the romfs file system in the Linux kernel did not properly validate file system     meta-data, leading to an out-of-bounds read. An attacker could use this to construct a malicious romfs     image that, when mounted, exposed sensitive information (kernel memory). (CVE-2020-29371)

    Jann Horn discovered that the tty subsystem of the Linux kernel did not use consistent locking in some     situations, leading to a read-after-free vulnerability. A local attacker could use this to cause a denial     of service (system crash) or possibly expose sensitive information (kernel memory). (CVE-2020-29660)

    Jann Horn discovered a race condition in the tty subsystem of the Linux kernel in the locking for the     TIOCSPGRP ioctl(), leading to a use-after- free vulnerability. A local attacker could use this to cause a     denial of service (system crash) or possibly execute arbitrary code. (CVE-2020-29661)

    It was discovered that a race condition existed that caused the Linux kernel to not properly restrict exit     signal delivery. A local attacker could possibly use this to send signals to arbitrary processes.
    (CVE-2020-35508)

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.

This update syncs the RT kernel from the SUSE Linux Enterprise 15-SP2 codestream. This update was imported from the SUSE:SLE-15-SP2:Update update project.

The SUSE Linux Enterprise 15 SP2 RT kernel was updated to receive various security and bugfixes.

The following security bugs were fixed :

CVE-2020-15436: Fixed a use after free vulnerability in fs/block_dev.c which could have allowed local users to gain privileges or cause a denial of service (bsc#1179141).

CVE-2020-15437: Fixed a NULL pointer dereference which could have allowed local users to cause a denial of service(bsc#1179140).

CVE-2020-25669: Fixed a use-after-free read in sunkbd_reinit() (bsc#1178182).

CVE-2020-25705: Fixed A flaw in the way reply ICMP packets are limited in was found that allowed to quickly scan open UDP ports. This flaw allowed an off-path remote user to effectively bypassing source port UDP randomization. The highest threat from this vulnerability is to confidentiality and possibly integrity, because software and services that rely on UDP source port randomization (like DNS) are indirectly affected as well. Kernel versions may be vulnerable to this issue (bsc#1175721, bsc#1178782).

CVE-2020-27777: Restrict RTAS requests from userspace (bsc#1179107)

CVE-2020-27786: Fixed a use after free in kernel midi subsystem snd_rawmidi_kernel_read1() (bsc#1179601).

CVE-2020-28915: Fixed a buffer over-read in the fbcon code which could have been used by local attackers to read kernel memory (bsc#1178886).

CVE-2020-28941: Fixed an issue where local attackers on systems with the speakup driver could cause a local denial of service attack (bsc#1178740).

CVE-2020-29369: Fixed a race condition between certain expand functions (expand_downwards and expand_upwards) and page-table free operations from an munmap call, aka CID-246c320a8cfe (bnc#1173504 bsc#1179432).

CVE-2020-29371: Fixed uninitialized memory leaks to userspace (bsc#1179429).

CVE-2020-4788: Fixed an issue with IBM Power9 processors could have allowed a local user to obtain sensitive information from the data in the L1 cache under extenuating circumstances (bsc#1177666).

The update package also includes non-security fixes. See advisory for details.

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

The SUSE Linux Enterprise 15 SP2 kernel was updated to 3.12.31 to receive various security and bugfixes.

The following security bugs were fixed :

CVE-2020-15436: Fixed a use after free vulnerability in fs/block_dev.c which could have allowed local users to gain privileges or cause a denial of service (bsc#1179141).

CVE-2020-15437: Fixed a NULL pointer dereference which could have allowed local users to cause a denial of service(bsc#1179140).

CVE-2020-25668: Fixed a concurrency use-after-free in con_font_op (bsc#1178123).

CVE-2020-25669: Fixed a use-after-free read in sunkbd_reinit() (bsc#1178182).

CVE-2020-25704: Fixed a leak in perf_event_parse_addr_filter() (bsc#1178393).

CVE-2020-27777: Restrict RTAS requests from userspace (bsc#1179107)

CVE-2020-28915: Fixed a buffer over-read in the fbcon code which could have been used by local attackers to read kernel memory (bsc#1178886).

CVE-2020-28974: Fixed a slab-out-of-bounds read in fbcon which could have been used by local attackers to read privileged information or potentially crash the kernel (bsc#1178589).

CVE-2020-29371: Fixed uninitialized memory leaks to userspace (bsc#1179429).

CVE-2020-25705: Fixed an issue which could have allowed to quickly scan open UDP ports. This flaw allowed an off-path remote user to effectively bypassing source port UDP randomization (bsc#1175721).

CVE-2020-28941: Fixed an issue where local attackers on systems with the speakup driver could cause a local denial of service attack (bsc#1178740).

CVE-2020-4788: Fixed an issue with IBM Power9 processors could have allowed a local user to obtain sensitive information from the data in the L1 cache under extenuating circumstances (bsc#1177666).

CVE-2020-29369: Fixed a race condition between certain expand functions (expand_downwards and expand_upwards) and page-table free operations from an munmap call, aka CID-246c320a8cfe (bnc#1173504 1179432).

The update package also includes non-security fixes. See advisory for details.

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

ID	Name	Product	Family	Severity
147982	Ubuntu 20.04 LTS : Linux kernel (OEM) vulnerabilities (USN-4752-1)	Nessus	Ubuntu Local Security Checks	high
146282	openSUSE Security Update : RT kernel (openSUSE-2021-242)	Nessus	SuSE Local Security Checks	critical
144313	openSUSE Security Update : the Linux Kernel (openSUSE-2020-2260)	Nessus	SuSE Local Security Checks	high
144143	SUSE SLES15 Security Update : kernel (SUSE-SU-2020:3764-1)	Nessus	SuSE Local Security Checks	high
144101	SUSE SLED15 / SLES15 Security Update : kernel (SUSE-SU-2020:3748-1)	Nessus	SuSE Local Security Checks	high
143523	openSUSE Security Update : the Linux Kernel (openSUSE-2020-2161)	Nessus	SuSE Local Security Checks	high

Detections

Analytics

CVE-2020-29369

high

Tenable Plugins

high

critical

high

high

high

high