CVE-2026-90393
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Received - Intake
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Vulnerability report for CVE-2026-90393, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-09-17
Last updated on: 2026-09-17
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
bpf: Fix potential UAF in bpf_netns_link_update_prog
In bpf_netns_link_update_prog, the checks for old_prog and prog type
are currently performed locklessly before acquiring netns_bpf_mutex.
This creates a race condition that can lead to a UAF issue.
If two threads concurrently execute BPF_LINK_UPDATE on the same netns
link, the following execution path can trigger a UAF:
CPU0 CPU1
bpf_netns_link_update_prog
if (old_prog && old_prog != link->prog)
return -EPERM;
bpf_netns_link_update_prog
if (old_prog && old_prog != link->prog)
...
old_prog = xchg(&link->prog, new_prog);
bpf_prog_put(old_prog);
if (new_prog->type != link->prog->type) <-- trigger UAF
Fix this by moving the old_prog and prog->type checks inside the
netns_bpf_mutex critical section. Meanwhile, use guard() to simplify
lock management and avoid all the goto jumping.
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
Currently, no data is known.
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
