CVE-2026-46086

Advisory lineage Upstream: 0 Downstream: 10
Awaiting Analysis
Published: 27 May 2026, 12:58
Last modified:19 Jun 2026, 11:59

Vulnerability Summary

Overall Risk (default)
minimal
0/100
CVSS Score
No data
EPSS Score
0.12% LOW
0% probability 0.00%
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

27 May 2026, 12:58
Published
Vulnerability first disclosed
19 Jun 2026, 11:59
Last Modified
Vulnerability information updated

Description

In the Linux kernel, the following vulnerability has been resolved: net: bridge: use a stable FDB dst snapshot in RCU readers Local FDB entries can be rewritten in place by `fdb_delete_local()`, which updates `f->dst` to another port or to `NULL` while keeping the entry alive. Several bridge RCU readers inspect `f->dst`, including `br_fdb_fillbuf()` through the `brforward_read()` sysfs path. These readers currently load `f->dst` multiple times and can therefore observe inconsistent values across the check and later dereference. In `br_fdb_fillbuf()`, this means a concurrent local-FDB update can change `f->dst` after the NULL check and before the `port_no` dereference, leading to a NULL-ptr-deref. Fix this by taking a single `READ_ONCE()` snapshot of `f->dst` in each affected RCU reader and using that snapshot for the rest of the access sequence. Also publish the in-place `f->dst` updates in `fdb_delete_local()` with `WRITE_ONCE()` so the readers and writer use matching access patterns.

EPSS Trends

Current EPSS score: 0.12%• Percentile: 2%

Affected Systems

  • linux•linux

    ≥ 960b589f86c74ce582922fcb996103271081f4de, < c502fa9f094cb03d1d1685c71e2105ab359bc2b8 | ≥ 960b589f86c74ce582922fcb996103271081f4de, < a6ae4511c07b91f597e461406c6330f0d4ff810e | ≥ 960b589f86c74ce582922fcb996103271081f4de, < 1406c4e0ed1eaf8a29801ab1163d00fb7ee4359a | ≥ 960b589f86c74ce582922fcb996103271081f4de, < 0b9e4bbfb7c949151e3acd44ed4aa33614d2e110 | ≥ 960b589f86c74ce582922fcb996103271081f4de, < 81af4137a30c4c2dc694dea8cacb180bd66000ef | ≥ 960b589f86c74ce582922fcb996103271081f4de, < 5424e678f9b304e148cf5dcc047cffc7a56a3bb5 | ≥ 960b589f86c74ce582922fcb996103271081f4de, < 9a2d9d4e657b23dc21f24cf139e3aeff0b61341f | ≥ 960b589f86c74ce582922fcb996103271081f4de, < df4601653201de21b487c3e7fffd464790cab808 | 3.14

References (8)