Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix potential UAF when reading bpf link info In bpf_link_show_fdinfo and bpf_link_get_info_by_fd, link->prog is accessed without holding any locks. If the prog is concurrently replaced via bpf_link_update, the old prog can be freed, leading to a potential UAF issue. Fix this by accessing link->prog under RCU protection to safely fetch the pointer and guarantee its lifetime while reading its fields.
References6
- git.kernel.org/stable/c/4c8432a332d4a24dc2742f56062a53d8fad36f53
- git.kernel.org/stable/c/79347e42cfbc9e78872922e8f08a70609c9af82f
- git.kernel.org/stable/c/85cf991c881e7198be32be05a9daa2625390c8b3
- git.kernel.org/stable/c/863f3ddd0b8ac65abfb50d3be0869268ac0e277b
- git.kernel.org/stable/c/a5c936ac904767fc1d943d40b0308bcb2ae2509b
- git.kernel.org/stable/c/d7d7208e2603b45724b684f4df73904fb347741e
Metrics
- CVSS 3.1
-
7.8
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 0% percentile: 6 · as of 8 November 2026
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.