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).
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).
Published:
2026-07-27
Score:
n/a
EPSS:
n/a
KEV:
No
Impact:
n/a
Action:
n/a
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Remediation
No vendor fix or workaround currently provided.
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Tracking
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Advisories
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References
History
Mon, 27 Jul 2026 20:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| 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). | |
| Title | bridge: cfm: reject invalid CCM interval at configuration time | |
| First Time appeared |
Linux
Linux linux Kernel |
|
| CPEs | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Linux
Linux linux Kernel |
|
| References |
|
|
Status: PUBLISHED
Assigner: Linux
Published:
Updated: 2026-07-27T20:10:32.210Z
Reserved: 2026-07-19T15:36:31.795Z
Link: CVE-2026-64537
No data.
No data.
No data.
OpenCVE Enrichment
No data.
Weaknesses
No weakness.