CVE-2026-74659

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-74659", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.924Z", "datePublished": "2026-08-22T15:32:32.926Z", "dateUpdated": "2026-08-22T15:32:32.926Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-22T15:32:32.926Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: mrp: fix uninitialised bytes on the wire\n\nbr_mrp_alloc_test_skb() builds MRP test frames on an skb from\ndev_alloc_skb(), which does not clear the linear data area. On the MRA\nring-role branch the sub-option TLV header is appended with\n\n\tsub_tlv = skb_put(skb, sizeof(*sub_tlv));\n\tsub_tlv->type = BR_MRP_SUB_TLV_HEADER_TEST_AUTO_MGR;\n\nso sub_tlv->length is never written, and the two trailing alignment bytes\nare appended with a bare skb_put() that does not clear them either. The\nneighbouring oui and sub_opt regions are explicitly zeroed, so three\nuninitialised bytes are left in every MRA MRP_Test frame that goes out.\n\nPut the sub-option TLV header and the alignment padding in a single\nskb_put_zero(), which clears both. The AUTO_MGR sub-TLV carries no\npayload, so the zeroed length field is already the value it should have."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/bridge/br_mrp.c"], "versions": [{"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "014c062d23c63ec77ef2cf17a0d9363c7441cc94", "status": "affected", "versionType": "git"}, {"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "7ebc23ff03668042e0b0e4034bb1518d36198d9e", "status": "affected", "versionType": "git"}, {"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "06d58b8d2f053ced82e01efaeb6e7c82891eed58", "status": "affected", "versionType": "git"}, {"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "a5e385eeb2d6dbbbdebfa050e67c34734ae12693", "status": "affected", "versionType": "git"}, {"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "5912cf1822fbe53ae275c147868740eb384a5d3e", "status": "affected", "versionType": "git"}, {"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "e08665218040f8e312abe40f74543186f3c2c941", "status": "affected", "versionType": "git"}, {"version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "lessThan": "63488dba65ef91373ef616575b32eb0eb21459f4", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["net/bridge/br_mrp.c"], "versions": [{"version": "5.14", "status": "affected"}, {"version": "0", "lessThan": "5.14", "status": "unaffected", "versionType": "semver"}, {"version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.152", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.104", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.18.45", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.1.9", "lessThanOrEqual": "7.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "7.2", "lessThanOrEqual": "*", "status": "unaffected", "versionType": "original_commit_for_fix"}]}], "cpeApplicability": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "5.15.216"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.1.183"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.6.152"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.12.104"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "6.18.45"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "7.1.9"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.14", "versionEndExcluding": "7.2"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/014c062d23c63ec77ef2cf17a0d9363c7441cc94"}, {"url": "https://git.kernel.org/stable/c/7ebc23ff03668042e0b0e4034bb1518d36198d9e"}, {"url": "https://git.kernel.org/stable/c/06d58b8d2f053ced82e01efaeb6e7c82891eed58"}, {"url": "https://git.kernel.org/stable/c/a5e385eeb2d6dbbbdebfa050e67c34734ae12693"}, {"url": "https://git.kernel.org/stable/c/5912cf1822fbe53ae275c147868740eb384a5d3e"}, {"url": "https://git.kernel.org/stable/c/e08665218040f8e312abe40f74543186f3c2c941"}, {"url": "https://git.kernel.org/stable/c/63488dba65ef91373ef616575b32eb0eb21459f4"}], "title": "net: bridge: mrp: fix uninitialised bytes on the wire", "x_generator": {"engine": "bippy-1.2.0"}}}}

{}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["net/bridge/br_mrp.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "014c062d23c63ec77ef2cf17a0d9363c7441cc94", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}, {"lessThan": "7ebc23ff03668042e0b0e4034bb1518d36198d9e", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}, {"lessThan": "06d58b8d2f053ced82e01efaeb6e7c82891eed58", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}, {"lessThan": "a5e385eeb2d6dbbbdebfa050e67c34734ae12693", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}, {"lessThan": "5912cf1822fbe53ae275c147868740eb384a5d3e", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}, {"lessThan": "e08665218040f8e312abe40f74543186f3c2c941", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}, {"lessThan": "63488dba65ef91373ef616575b32eb0eb21459f4", "status": "affected", "version": "f7458934b0791c39a001e4d902fc3bf697b439b5", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["net/bridge/br_mrp.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"status": "affected", "version": "5.14"}, {"lessThan": "5.14", "status": "unaffected", "version": "0", "versionType": "semver"}, {"lessThanOrEqual": "5.15.*", "status": "unaffected", "version": "5.15.216", "versionType": "semver"}, {"lessThanOrEqual": "6.1.*", "status": "unaffected", "version": "6.1.183", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.152", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.104", "versionType": "semver"}, {"lessThanOrEqual": "6.18.*", "status": "unaffected", "version": "6.18.45", "versionType": "semver"}, {"lessThanOrEqual": "7.1.*", "status": "unaffected", "version": "7.1.9", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "7.2", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet: bridge: mrp: fix uninitialised bytes on the wire\n\nbr_mrp_alloc_test_skb() builds MRP test frames on an skb from\ndev_alloc_skb(), which does not clear the linear data area. On the MRA\nring-role branch the sub-option TLV header is appended with\n\n\tsub_tlv = skb_put(skb, sizeof(*sub_tlv));\n\tsub_tlv->type = BR_MRP_SUB_TLV_HEADER_TEST_AUTO_MGR;\n\nso sub_tlv->length is never written, and the two trailing alignment bytes\nare appended with a bare skb_put() that does not clear them either. The\nneighbouring oui and sub_opt regions are explicitly zeroed, so three\nuninitialised bytes are left in every MRA MRP_Test frame that goes out.\n\nPut the sub-option TLV header and the alignment padding in a single\nskb_put_zero(), which clears both. The AUTO_MGR sub-TLV carries no\npayload, so the zeroed length field is already the value it should have."}, {"lang": "es", "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nnet: bridge: mrp: corregir bytes no inicializados en la red\n\nbr_mrp_alloc_test_skb() construye tramas de prueba MRP en un skb de dev_alloc_skb(), que no borra el \u00e1rea de datos lineal. En la rama de rol de anillo MRA, la cabecera TLV de subopci\u00f3n se a\u00f1ade con\n\nsub_tlv = skb_put(skb, sizeof(sub_tlv));\nsub_tlv -> type = BR_MRP_SUB_TLV_HEADER_TEST_AUTO_MGR;\n\npor lo que sub_tlv -> length nunca se escribe, y los dos bytes de alineaci\u00f3n finales se a\u00f1aden con un skb_put() simple que tampoco los borra. Las regiones oui y sub_opt vecinas se ponen expl\u00edcitamente a cero, por lo que quedan tres bytes no inicializados en cada trama MRA MRP_Test que sale.\n\nPoner la cabecera TLV de subopci\u00f3n y el relleno de alineaci\u00f3n en un \u00fanico skb_put_zero(), que borra ambos. El sub-TLV AUTO_MGR no lleva carga \u00fatil, por lo que el campo de longitud puesto a cero ya es el valor que deber\u00eda tener."}], "id": "CVE-2026-74659", "lastModified": "2026-10-14T13:10:00.187", "metrics": {}, "published": "2026-08-22T16:16:39.613", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/014c062d23c63ec77ef2cf17a0d9363c7441cc94"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/06d58b8d2f053ced82e01efaeb6e7c82891eed58"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/5912cf1822fbe53ae275c147868740eb384a5d3e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/63488dba65ef91373ef616575b32eb0eb21459f4"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/7ebc23ff03668042e0b0e4034bb1518d36198d9e"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/a5e385eeb2d6dbbbdebfa050e67c34734ae12693"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/e08665218040f8e312abe40f74543186f3c2c941"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Received"}

{"bugzilla": {"description": "kernel: net: bridge: mrp: fix uninitialised bytes on the wire", "id": "2521462", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2521462"}, "csaw": false, "cvss3": {"cvss3_base_score": "5.5", "cvss3_scoring_vector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "status": "draft"}, "cwe": "CWE-824", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nnet: bridge: mrp: fix uninitialised bytes on the wire\nbr_mrp_alloc_test_skb() builds MRP test frames on an skb from\ndev_alloc_skb(), which does not clear the linear data area. On the MRA\nring-role branch the sub-option TLV header is appended with\nsub_tlv = skb_put(skb, sizeof(*sub_tlv));\nsub_tlv->type = BR_MRP_SUB_TLV_HEADER_TEST_AUTO_MGR;\nso sub_tlv->length is never written, and the two trailing alignment bytes\nare appended with a bare skb_put() that does not clear them either. The\nneighbouring oui and sub_opt regions are explicitly zeroed, so three\nuninitialised bytes are left in every MRA MRP_Test frame that goes out.\nPut the sub-option TLV header and the alignment padding in a single\nskb_put_zero(), which clears both. The AUTO_MGR sub-TLV carries no\npayload, so the zeroed length field is already the value it should have.", "A flaw was found in the Linux kernel's Multiple Registration Protocol (MRP) bridge module. When constructing MRP test frames, the br_mrp_alloc_test_skb() function fails to properly initialize certain fields. This oversight results in three uninitialized bytes being transmitted in every MRA MRP_Test frame, potentially leading to the disclosure of sensitive information."], "name": "CVE-2026-74659", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:6", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 9"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Not affected", "package_name": "kernel-rt", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-08-22T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-74659\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-74659\nhttps://lore.kernel.org/linux-cve-announce/2026082227-CVE-2026-74659-16e5@gregkh/T"], "threat_severity": "Moderate"}

{"affected": [{"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,014c062d23c63ec77ef2cf17a0d9363c7441cc94)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,7ebc23ff03668042e0b0e4034bb1518d36198d9e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,06d58b8d2f053ced82e01efaeb6e7c82891eed58)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,a5e385eeb2d6dbbbdebfa050e67c34734ae12693)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,5912cf1822fbe53ae275c147868740eb384a5d3e)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,e08665218040f8e312abe40f74543186f3c2c941)"}}, {"platform": null, "status": "affected", "versions": {"scheme": "code_commit", "value": "[f7458934b0791c39a001e4d902fc3bf697b439b5,63488dba65ef91373ef616575b32eb0eb21459f4)"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}, {"configurations": [{"platform": null, "status": "affected", "versions": {"scheme": "semver", "value": "5.14"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[0,5.14)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[5.15.216,5.16.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.1.183,6.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.6.152,6.7.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.12.104,6.13.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[6.18.45,6.19.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "semver", "value": "[7.1.9,7.2.0)"}}, {"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[0,*]"}}], "enrichment": {"confidence": 99.0, "confidence_source": "inferred", "scores": [{"score": 99.0, "source": "inferred"}, {"score": 100.0, "source": "matching"}]}, "original": {"product": "Linux", "source": "cna", "vendor": "Linux"}, "product": "linux_kernel", "vendor": "linux"}], "created": "2026-08-22T19:30:17.494911+00:00", "updated": "2026-08-25T14:00:17.978377+00:00", "vendors": ["linux", "linux$PRODUCT$linux_kernel"], "weaknesses": ["CWE-758", "CWE-788", "CWE-824"]}