Description
In the Linux kernel, the following vulnerability has been resolved:
bridge: cfm: reject invalid CCM interval at configuration time
ccm_tx_work_expired() re-arms itself via queue_delayed_work() using the configured exp_interval converted by interval_to_us(). When exp_interval is BR_CFM_CCM_INTERVAL_NONE or out of range, interval_to_us() returns 0, causing the worker to fire immediately in a tight loop that allocates skbs until OOM.
Fix this by validating exp_interval at configuration time:
- Constrain IFLA_BRIDGE_CFM_CC_CONFIG_EXP_INTERVAL to the valid range [BR_CFM_CCM_INTERVAL_3_3_MS, BR_CFM_CCM_INTERVAL_10_MIN] in the netlink policy so userspace cannot set an invalid value.
- Reject starting CCM TX in br_cfm_cc_ccm_tx() when exp_interval has not yet been configured (defaults to 0 from kzalloc).
Metrics
No CVSS score has been published yet.
Affected software
Source: the vendor's advisory (CNA). NVD analysis pending.
| Vendor | Product | Versions |
|---|---|---|
| Linux | Linux | >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < 2870056a78961e0fecd652362ee9d3fcfd24a8a6; >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < f0f5eb59a97ece0d85de8cfa95dc18c609302a8b; >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < 53788b134519e995699ea3721969c96a08d64575; >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < b42aeb58317f12024734759ff745856b53948873; >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < a090880c1f544589427e5b7050c40fb211ccecb4; >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < 865643640b5b5c4579b32d7a55ac9ad648362eaa; >= 2be665c3940d367e0a2a8128eb4985ce323f99a3, < f3e02edd8322b31b8e6517faa6ba053bf29d1e26 |
| Linux | Linux | 5.11 |
References
- https://git.kernel.org/stable/c/2870056a78961e0fecd652362ee9d3fcfd24a8a6
- https://git.kernel.org/stable/c/53788b134519e995699ea3721969c96a08d64575
- https://git.kernel.org/stable/c/865643640b5b5c4579b32d7a55ac9ad648362eaa
- https://git.kernel.org/stable/c/a090880c1f544589427e5b7050c40fb211ccecb4
- https://git.kernel.org/stable/c/b42aeb58317f12024734759ff745856b53948873
- https://git.kernel.org/stable/c/f0f5eb59a97ece0d85de8cfa95dc18c609302a8b
- https://git.kernel.org/stable/c/f3e02edd8322b31b8e6517faa6ba053bf29d1e26
Timeline
- Published
- Jul 27, 2026
- Last modified
- Nov 3, 2026
- NVD status
- Undergoing Analysis