{"api_version":"1","generated_at":"2026-08-05T22:23:07+00:00","cve":"CVE-2026-64537","urls":{"html":"https://cve.report/CVE-2026-64537","api":"https://cve.report/api/cve/CVE-2026-64537.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-64537","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-64537"},"summary":{"title":"bridge: cfm: reject invalid CCM interval at configuration time","description":"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).","state":"PUBLISHED","assigner":"Linux","published_at":"2026-07-27 21:17:05","updated_at":"2026-07-27 21:17:05"},"problem_types":[],"metrics":[],"references":[{"url":"https://git.kernel.org/stable/c/f3e02edd8322b31b8e6517faa6ba053bf29d1e26","name":"https://git.kernel.org/stable/c/f3e02edd8322b31b8e6517faa6ba053bf29d1e26","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/53788b134519e995699ea3721969c96a08d64575","name":"https://git.kernel.org/stable/c/53788b134519e995699ea3721969c96a08d64575","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/b42aeb58317f12024734759ff745856b53948873","name":"https://git.kernel.org/stable/c/b42aeb58317f12024734759ff745856b53948873","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/865643640b5b5c4579b32d7a55ac9ad648362eaa","name":"https://git.kernel.org/stable/c/865643640b5b5c4579b32d7a55ac9ad648362eaa","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/f0f5eb59a97ece0d85de8cfa95dc18c609302a8b","name":"https://git.kernel.org/stable/c/f0f5eb59a97ece0d85de8cfa95dc18c609302a8b","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/a090880c1f544589427e5b7050c40fb211ccecb4","name":"https://git.kernel.org/stable/c/a090880c1f544589427e5b7050c40fb211ccecb4","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/2870056a78961e0fecd652362ee9d3fcfd24a8a6","name":"https://git.kernel.org/stable/c/2870056a78961e0fecd652362ee9d3fcfd24a8a6","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-64537","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64537","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 2870056a78961e0fecd652362ee9d3fcfd24a8a6 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 f0f5eb59a97ece0d85de8cfa95dc18c609302a8b git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 53788b134519e995699ea3721969c96a08d64575 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 b42aeb58317f12024734759ff745856b53948873 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 a090880c1f544589427e5b7050c40fb211ccecb4 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 865643640b5b5c4579b32d7a55ac9ad648362eaa git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 2be665c3940d367e0a2a8128eb4985ce323f99a3 f3e02edd8322b31b8e6517faa6ba053bf29d1e26 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 5.11","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.11 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 5.15.212 5.15.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.1.178 6.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.6.145 6.6.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.97 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.40 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.1.5 7.1.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2-rc1 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":{"cve_year":"2026","cve_id":"64537","cve":"CVE-2026-64537","epss":"0.001720000","percentile":"0.068950000","score_date":"2026-07-29","updated_at":"2026-07-30 00:09:14"},"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/bridge/br_cfm.c","net/bridge/br_cfm_netlink.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"2870056a78961e0fecd652362ee9d3fcfd24a8a6","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"},{"lessThan":"f0f5eb59a97ece0d85de8cfa95dc18c609302a8b","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"},{"lessThan":"53788b134519e995699ea3721969c96a08d64575","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"},{"lessThan":"b42aeb58317f12024734759ff745856b53948873","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"},{"lessThan":"a090880c1f544589427e5b7050c40fb211ccecb4","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"},{"lessThan":"865643640b5b5c4579b32d7a55ac9ad648362eaa","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"},{"lessThan":"f3e02edd8322b31b8e6517faa6ba053bf29d1e26","status":"affected","version":"2be665c3940d367e0a2a8128eb4985ce323f99a3","versionType":"git"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/bridge/br_cfm.c","net/bridge/br_cfm_netlink.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"status":"affected","version":"5.11"},{"lessThan":"5.11","status":"unaffected","version":"0","versionType":"semver"},{"lessThanOrEqual":"5.15.*","status":"unaffected","version":"5.15.212","versionType":"semver"},{"lessThanOrEqual":"6.1.*","status":"unaffected","version":"6.1.178","versionType":"semver"},{"lessThanOrEqual":"6.6.*","status":"unaffected","version":"6.6.145","versionType":"semver"},{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.97","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.40","versionType":"semver"},{"lessThanOrEqual":"7.1.*","status":"unaffected","version":"7.1.5","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2-rc1","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"5.15.212","versionStartIncluding":"5.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.1.178","versionStartIncluding":"5.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.6.145","versionStartIncluding":"5.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.97","versionStartIncluding":"5.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.40","versionStartIncluding":"5.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.1.5","versionStartIncluding":"5.11","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2-rc1","versionStartIncluding":"5.11","vulnerable":true}],"negate":false,"operator":"OR"}]}],"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":"2026-07-27T20:10:32.210Z","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":{"engine":"bippy-1.2.0"}}},"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":"2026-07-27T20:10:32.210Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-07-27 21:17:05","lastModifiedDate":"2026-07-27 21:17:05","problem_types":[],"metrics":[],"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"64537","Ordinal":"1","Title":"bridge: cfm: reject invalid CCM interval at configuration time","CVE":"CVE-2026-64537","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"64537","Ordinal":"1","NoteData":"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).","Type":"Description","Title":"bridge: cfm: reject invalid CCM interval at configuration time"}]}}}