Answer in brief
CVE-2026-64537 records a Unknown severity vulnerability in bridge: cfm: reject invalid CCM interval at configuration time. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-64537 records a Unknown severity vulnerability in bridge: cfm: reject invalid CCM interval at configuration time. The current sources do not mark it as known exploited. The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <2870056a78961e0fecd652362ee9d3fcfd24a8a6 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <f0f5eb59a97ece0d85de8cfa95dc18c609302a8b || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <53788b134519e995699ea3721969c96a08d64575 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <b42aeb58317f12024734759ff745856b53948873 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <a090880c1f544589427e5b7050c40fb211ccecb4 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <865643640b5b5c4579b32d7a55ac9ad648362eaa || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <f3e02edd8322b31b8e6517faa6ba053bf29d1e26 | 2870056a78961e0fecd652362ee9d3fcfd24a8a6, f0f5eb59a97ece0d85de8cfa95dc18c609302a8b, 53788b134519e995699ea3721969c96a08d64575, b42aeb58317f12024734759ff745856b53948873, a090880c1f544589427e5b7050c40fb211ccecb4, 865643640b5b5c4579b32d7a55ac9ad648362eaa, f3e02edd8322b31b8e6517faa6ba053bf29d1e26 |
| Linux/Linuxgeneric | 5.11 | Not reported |
Published upstream
Jul 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 17, 2026
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).
Quoted source text, attributed separately from HOL analysis.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Linux/Linux (generic), Linux/Linux (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Linux/Linuxgeneric | >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <2870056a78961e0fecd652362ee9d3fcfd24a8a6 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <f0f5eb59a97ece0d85de8cfa95dc18c609302a8b || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <53788b134519e995699ea3721969c96a08d64575 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <b42aeb58317f12024734759ff745856b53948873 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <a090880c1f544589427e5b7050c40fb211ccecb4 || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <865643640b5b5c4579b32d7a55ac9ad648362eaa || >=2be665c3940d367e0a2a8128eb4985ce323f99a3 <f3e02edd8322b31b8e6517faa6ba053bf29d1e26 | 2870056a78961e0fecd652362ee9d3fcfd24a8a6, f0f5eb59a97ece0d85de8cfa95dc18c609302a8b, 53788b134519e995699ea3721969c96a08d64575, b42aeb58317f12024734759ff745856b53948873, a090880c1f544589427e5b7050c40fb211ccecb4, 865643640b5b5c4579b32d7a55ac9ad648362eaa, f3e02edd8322b31b8e6517faa6ba053bf29d1e26 |
| Linux/Linuxgeneric | 5.11 | Not reported |
Published upstream
Jul 27, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 17, 2026
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).
Quoted source text, attributed separately from HOL analysis.