Use After Free in Linux

CVE-2026-52912

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_queue: hold bridge skb->dev while queued br_pass_frame_up() rewrites skb->dev from the ingress port to the bridge master before queueing bridge LOCAL_IN packets. NFQUEUE only holds references on state.in/out and bridge physdevs, so a queued bridge packet can retain a freed bridge master in skb->dev until reinjection. When the verdict is reinjected later, br_netif_receive_skb() re-enters the receive path with skb->dev still pointing at the freed bridge master, triggering a use-after-free. Store skb->dev in the queue entry, hold a reference on it for the queue lifetime, and use the saved device when dropping queued packets during NETDEV_DOWN handling.

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: 0.002 (3.7th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 4th percentile — 3.7% 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-2026-52912: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.000

Affected products

  • Linux — versions ac28634456867b23b95faccba7997a62ec430603, 4.7, 0
  • Linux Kernel — versions 7.1

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-52912?
CVE-2026-52912 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2026-06-24.
How severe is CVE-2026-52912?
High severity. CVSS v3 base score is 7.8 out of 10.