CVE-2026-74480

net: bridge: stop fast-leave after deleting a port group

CRITICAL 9.8

At a glance

Source
NVD
EPSS
EPSS 0.58 % · percentile 48 ()
State
PUBLISHED
Published
Updated
Assigner
Linux
NVD status
Received

Description

In the Linux kernel, the following vulnerability has been resolved: net: bridge: stop fast-leave after deleting a port group br_multicast_leave_group() iterates mp->ports with pp = &p->next in its fast-leave path. After br_multicast_del_pg() removes p, continuing the loop advances pp through the deleted entry. If multicast-to-unicast was enabled, the bridge can hold multiple port groups for the same port and group with different source MAC addresses. Once multicast-to-unicast is disabled, br_port_group_equal() matches those entries by port only. A fast leave can then delete one entry and continue from its stale next pointer, leaving mp->ports pointing at a deleted port group. Fast leave only needs to remove one matching port group. Break after br_multicast_del_pg() so the loop stops before dereferencing the removed entry.

References

Scores

VersionScoreVectorScored by
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HLinux
CVSS 3.1CRITICAL 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HNVD · 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Secondary)

European references

CERT-FR advisories

Affected products

ProductVersions
Linux · Linuxaffected 6db6f0eae6052b70885562e1733896647ec1d807 < d6c32e2e25a9a06ba021030e26b6d602a277eb72 ; affected 6db6f0eae6052b70885562e1733896647ec1d807 < 482bcb85139addb4e8ac8ed10baeda3e0aad4031 ; affected 6db6f0eae6052b70885562e1733896647ec1d807 < 1a109cc9890d017c41d77e6c82da739579c49f0b ; affected 6db6f0eae6052b70885562e1733896647ec1d807 < 159ad90cb929c033308bb39a2c5f8fbf393b77aa ; affected 6db6f0eae6052b70885562e1733896647ec1d807 < 4695430e8132420bf8de94da3eb36a6cf35fde6b ; affected 6db6f0eae6052b70885562e1733896647ec1d807 < 0309ebbc570000ea0df11c06b69798e5860c5f6f
Linux · Linuxaffected 4.11 ; unaffected 0 < 4.11 ; unaffected 5.10.265 ≤ 5.10.* ; unaffected 5.15.216 ≤ 5.15.* ; unaffected 6.1.183 ≤ 6.1.* ; unaffected 6.6.151 ≤ 6.6.*

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD