PT-2021-5068 · Linux+3 · Linux Kernel+3

Jann Horn · Published 2021-09-23 · Updated 2023-08-14 · CVE-2021-43057

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel versions prior to 5.14.8

Description A use-after-free issue in the selinux ptrace traceme() function, which is the SELinux handler for PTRACE TRACEME, could allow local attackers to cause memory corruption and escalate privileges. This occurs due to an attempt to access the subjective credentials of another task.

Recommendations For versions prior to 5.14.8, update to version 5.14.8 or later to resolve the issue. As a temporary workaround, consider restricting access to the selinux ptrace traceme() function to minimize the risk of exploitation.

Exploit

Fix

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

ALT-PU-2021-2902

ALT-PU-2021-2926

ALT-PU-2021-3041

ALT-PU-2023-4894

AZL-6602

BDU:2021-05848

CVE-2021-43057

USN-5162-1

Affected Products

Alt Linux

Linuxmint

Linux Kernel

Ubuntu

References · 23

• 🔥 https://bugs.chromium.org/p/project-zero/issues/detail?id=2229 · Exploit
• https://ubuntu.com/security/CVE-2021-42252 · Vendor Advisory
• https://osv.dev/vulnerability/AZL-6602 · Vendor Advisory
• https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.14.8 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2021-43057 · Security Note
• https://ubuntu.com/security/CVE-2021-43057 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-5162-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-3655 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2021-43057 · Security Note
• https://ubuntu.com/security/CVE-2021-3764 · Vendor Advisory
• https://ubuntu.com/security/CVE-2021-3744 · Vendor Advisory
• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=a3727a8bac0a9e77c70820655fd8715523ba3db7 · Vendor Advisory
• https://osv.dev/vulnerability/UBUNTU-CVE-2021-43057 · Vendor Advisory
• https://osv.dev/vulnerability/DEBIAN-CVE-2021-43057 · Vendor Advisory
• https://security-tracker.debian.org/tracker/CVE-2021-43057 · Vendor Advisory