CVE-2023-1281: UAF in Linux kernel's tcindex (traffic control index filter) implementation

Severity: high (CVSS 7.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2023-03-22 · updated 2026-07-30
Weakness: CWE-416

Description

Use After Free vulnerability in Linux kernel traffic control index filter (tcindex) allows Privilege Escalation. The imperfect hash area can be updated while packets are traversing, which will cause a use-after-free when 'tcf_exts_exec()' is called with the destroyed tcf_ext. A local attacker user can use this vulnerability to elevate its privileges to root. This issue affects Linux Kernel: from 4.14 before git commit ee059170b1f7e94e55fa6cadee544e176a6e59c2.

Affected products

Linux kernel: from 4.14 before 5.10.169; from 5.11 before 5.15.95; from 5.16 before 6.1.13; 6.2-rc1, 6.2-rc2, 6.2-rc3, 6.2-rc4, 6.2-rc5, 6.2-rc6 (+2) — fixed in 5.10.169, 5.15.95, 6.1.13

How to fix

Upgrade to a fixed version: Linux kernel 5.10.169, 5.15.95, 6.1.13. Check the vendor advisory for mitigations.

References

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