CVE-2021-33909 Information

Description

fs/seq_file.c in the Linux kernel 3.16 through 5.13.x before 5.13.4 does not properly restrict seq buffer allocations leading to an integer overflow an Out-of-bounds Write and escalation to root by an unprivileged user aka CID-8cae8cd89f05.

CVSS Vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Reference

https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.13.4 https://github.com/torvalds/linux/commit/8cae8cd89f05f6de223d63e6d15e31c8ba9cf53b https://www.openwall.com/lists/oss-security/2021/07/20/1 https://lists.debian.org/debian-lts-announce/2021/07/msg00016.html https://lists.debian.org/debian-lts-announce/2021/07/msg00015.html https://lists.debian.org/debian-lts-announce/2021/07/msg00014.html https://www.debian.org/security/2021/dsa-4941 http://packetstormsecurity.com/files/163621/Sequoia-A-Deep-Root-In-Linuxs-Filesystem-Layer.html https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/Z4UHHIGISO3FVRF4CQNJS4IKA25ATSFU/ http://www.openwall.com/lists/oss-security/2021/07/22/7 http://packetstormsecurity.com/files/163671/Kernel-Live-Patch-Security-Notice-LSN-0079-1.html https://security.netapp.com/advisory/ntap-20210819-0004/ http://www.openwall.com/lists/oss-security/2021/08/25/10 http://packetstormsecurity.com/files/164155/Kernel-Live-Patch-Security-Notice-LSN-0081-1.html http://www.openwall.com/lists/oss-security/2021/09/17/2 http://www.openwall.com/lists/oss-security/2021/09/17/4 http://www.openwall.com/lists/oss-security/2021/09/21/1 http://packetstormsecurity.com/files/165477/Kernel-Live-Patch-Security-Notice-LSN-0083-1.html https://www.oracle.com/security-alerts/cpujan2022.html

Attack Complexity

LOW

Privileges Required

LOW

User Interaction Required

LOW

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

HIGH

Base Severity

7.8