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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HAffected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 6db6f0eae6052b70885562e1733896647ec1d807, < d6c32e2e25a9a06ba021030e26b6d602a277eb72; >= 6db6f0eae6052b70885562e1733896647ec1d807, < 482bcb85139addb4e8ac8ed10baeda3e0aad4031; >= 6db6f0eae6052b70885562e1733896647ec1d807, < 1a109cc9890d017c41d77e6c82da739579c49f0b; >= 6db6f0eae6052b70885562e1733896647ec1d807, < 159ad90cb929c033308bb39a2c5f8fbf393b77aa; >= 6db6f0eae6052b70885562e1733896647ec1d807, < 4695430e8132420bf8de94da3eb36a6cf35fde6b; >= 6db6f0eae6052b70885562e1733896647ec1d807, < 0309ebbc570000ea0df11c06b69798e5860c5f6f; >= 6db6f0eae6052b70885562e1733896647ec1d807, < 4c57056ca6aace2e9f94ae9298bf49ef6b0c95e4; >= 6db6f0eae6052b70885562e1733896647ec1d807, < a39789f211b8a4125f0c70e05b30cf715f4f187d |
| Linux | Linux | 4.11 |
References
- https://git.kernel.org/stable/c/0309ebbc570000ea0df11c06b69798e5860c5f6f
- https://git.kernel.org/stable/c/159ad90cb929c033308bb39a2c5f8fbf393b77aa
- https://git.kernel.org/stable/c/1a109cc9890d017c41d77e6c82da739579c49f0b
- https://git.kernel.org/stable/c/4695430e8132420bf8de94da3eb36a6cf35fde6b
- https://git.kernel.org/stable/c/482bcb85139addb4e8ac8ed10baeda3e0aad4031
- https://git.kernel.org/stable/c/4c57056ca6aace2e9f94ae9298bf49ef6b0c95e4
- https://git.kernel.org/stable/c/a39789f211b8a4125f0c70e05b30cf715f4f187d
- https://git.kernel.org/stable/c/d6c32e2e25a9a06ba021030e26b6d602a277eb72
Timeline
- Published
- Aug 15, 2026
- Last modified
- Oct 16, 2026
- NVD status
- Received