Use After Free in Linux

CVE-2022-49622

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: avoid skb access on nf_stolen When verdict is NF_STOLEN, the skb might have been freed. When tracing is enabled, this can result in a use-after-free: 1. access to skb->nf_trace 2. access to skb->mark 3. computation of trace id 4. dump of packet payload To avoid 1, keep a cached copy of skb->nf_trace in the trace state struct. Refresh this copy whenever verdict is != STOLEN. Avoid 2 by skipping skb->mark access if verdict is STOLEN. 3 is avoided by precomputing the trace id. Only dump the packet when verdict is not "STOLEN".

Vulnerability class: Use-After-Free

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.003 (15.4th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.4% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2022-49622: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000

Affected products

  • Linux — versions 5efa0fc6d7f7930b18801f07cefae8eeacd6ac02, 4.10, 0
  • Linux Kernel — versions 5.19

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2022-49622?
CVE-2022-49622 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2025-02-26.
How severe is CVE-2022-49622?
High severity. CVSS v3 base score is 7.8 out of 10.