Out-of-bounds write in Linux kernel - CVE-2021-22555
Published: August 20, 2021 / Updated: February 8, 2024
Vulnerability identifier: #VU56017
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:A/U:Clear
CVE-ID: CVE-2021-22555
CWE-ID: CWE-787
Exploitation vector: Local access
Exploit availability:
The vulnerability is being exploited in the wild
Vendor: Linux Foundation
Affected software:
Linux kernel
Linux kernel
Detailed vulnerability description
The vulnerability allows a local user to escalate privileges on the system.
The vulnerability exists due to a boundary error when processing untrusted input in net/netfilter/x_tables.c in Linux kernel. A local user can run a specially crafted program to trigger an out-of-bounds write and execute arbitrary code with elevated privileges.
How to mitigate CVE-2021-22555
Install updates from vendor's website.
Sources
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=b29c457a6511435960115c0f548c4360d5f4801d
- https://github.com/google/security-research/security/advisories/GHSA-xxx5-8mvq-3528
- https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/net/netfilter/x_tables.c?id=9fa492cdc160cd27ce1046cb36f47d3b2b1efa21
- http://packetstormsecurity.com/files/163528/Linux-Kernel-Netfilter-Heap-Out-Of-Bounds-Write.html
- https://security.netapp.com/advisory/ntap-20210805-0010/
- http://packetstormsecurity.com/files/163878/Kernel-Live-Patch-Security-Notice-LSN-0080-1.html