CVE-2026-64537 (GCVE-0-2026-64537)
Vulnerability from cvelistv5
Published
2026-07-27 20:10
Modified
2026-08-17 04:57
Severity ?
VLAI Severity ?
EPSS score ?
Summary
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).
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Linux | Linux |
Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 Version: 2be665c3940d367e0a2a8128eb4985ce323f99a3 |
||
{
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"net/bridge/br_cfm.c",
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"version": "5.15.212",
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},
{
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"status": "unaffected",
"version": "6.1.178",
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},
{
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"version": "6.6.145",
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},
{
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"version": "6.12.97",
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{
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},
{
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"status": "unaffected",
"version": "7.2",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
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"nodes": [
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"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbridge: cfm: reject invalid CCM interval at configuration time\n\nccm_tx_work_expired() re-arms itself via queue_delayed_work() using\nthe configured exp_interval converted by interval_to_us(). When\nexp_interval is BR_CFM_CCM_INTERVAL_NONE or out of range,\ninterval_to_us() returns 0, causing the worker to fire immediately in\na tight loop that allocates skbs until OOM.\n\nFix this by validating exp_interval at configuration time:\n\n - Constrain IFLA_BRIDGE_CFM_CC_CONFIG_EXP_INTERVAL to the valid range\n [BR_CFM_CCM_INTERVAL_3_3_MS, BR_CFM_CCM_INTERVAL_10_MIN] in the\n netlink policy so userspace cannot set an invalid value.\n\n - Reject starting CCM TX in br_cfm_cc_ccm_tx() when exp_interval has\n not yet been configured (defaults to 0 from kzalloc)."
}
],
"providerMetadata": {
"dateUpdated": "2026-08-17T04:57:13.368Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"shortName": "Linux"
},
"references": [
{
"url": "https://git.kernel.org/stable/c/2870056a78961e0fecd652362ee9d3fcfd24a8a6"
},
{
"url": "https://git.kernel.org/stable/c/f0f5eb59a97ece0d85de8cfa95dc18c609302a8b"
},
{
"url": "https://git.kernel.org/stable/c/53788b134519e995699ea3721969c96a08d64575"
},
{
"url": "https://git.kernel.org/stable/c/b42aeb58317f12024734759ff745856b53948873"
},
{
"url": "https://git.kernel.org/stable/c/a090880c1f544589427e5b7050c40fb211ccecb4"
},
{
"url": "https://git.kernel.org/stable/c/865643640b5b5c4579b32d7a55ac9ad648362eaa"
},
{
"url": "https://git.kernel.org/stable/c/f3e02edd8322b31b8e6517faa6ba053bf29d1e26"
}
],
"title": "bridge: cfm: reject invalid CCM interval at configuration time",
"x_generator": {
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}
},
"cveMetadata": {
"assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"assignerShortName": "Linux",
"cveId": "CVE-2026-64537",
"datePublished": "2026-07-27T20:10:32.210Z",
"dateReserved": "2026-07-19T15:36:31.795Z",
"dateUpdated": "2026-08-17T04:57:13.368Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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