CVE-2025-21658

{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2025-21658", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2024-12-29T08:45:45.731Z", "datePublished": "2025-01-21T12:18:14.578Z", "dateUpdated": "2026-10-30T12:20:41.665Z"}, "containers": {"cna": {"providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:20:41.665Z"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: avoid NULL pointer dereference if no valid extent tree\n\n[BUG]\nSyzbot reported a crash with the following call trace:\n\n BTRFS info (device loop0): scrub: started on devid 1\n BUG: kernel NULL pointer dereference, address: 0000000000000208\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0\n Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI\n CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206\n Tainted: [O]=OOT_MODULE\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022\n RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]\n Call Trace:\n <TASK>\n scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]\n scrub_simple_mirror+0x175/0x260 [btrfs]\n scrub_stripe+0x5d4/0x6c0 [btrfs]\n scrub_chunk+0xbb/0x170 [btrfs]\n scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]\n btrfs_scrub_dev+0x240/0x600 [btrfs]\n btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]\n ? do_sys_openat2+0xa5/0xf0\n __x64_sys_ioctl+0x97/0xc0\n do_syscall_64+0x4f/0x120\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n </TASK>\n\n[CAUSE]\nThe reproducer is using a corrupted image where extent tree root is\ncorrupted, thus forcing to use \"rescue=all,ro\" mount option to mount the\nimage.\n\nThen it triggered a scrub, but since scrub relies on extent tree to find\nwhere the data/metadata extents are, scrub_find_fill_first_stripe()\nrelies on an non-empty extent root.\n\nBut unfortunately scrub_find_fill_first_stripe() doesn't really expect\nan NULL pointer for extent root, it use extent_root to grab fs_info and\ntriggered a NULL pointer dereference.\n\n[FIX]\nAdd an extra check for a valid extent root at the beginning of\nscrub_find_fill_first_stripe().\n\nThe new error path is introduced by 42437a6386ff (\"btrfs: introduce\nmount option rescue=ignorebadroots\"), but that's pretty old, and later\ncommit b979547513ff (\"btrfs: scrub: introduce helper to find and fill\nsector info for a scrub_stripe\") changed how we do scrub.\n\nSo for kernels older than 6.6, the fix will need manual backport."}], "affected": [{"product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/btrfs/scrub.c"], "versions": [{"version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "1fb37b7840fdcbf69d062a79d14afbf566b11873", "status": "affected", "versionType": "git"}, {"version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "24b85a8b0310e0144da9ab30be42e87e6476638a", "status": "affected", "versionType": "git"}, {"version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "aee5f69f3e6cd82bfefaca1b70b40b6cd8f3f784", "status": "affected", "versionType": "git"}, {"version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "6aecd91a5c5b68939cf4169e32bc49f3cd2dd329", "status": "affected", "versionType": "git"}]}, {"product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": ["fs/btrfs/scrub.c"], "versions": [{"version": "5.11", "status": "affected"}, {"version": "0", "lessThan": "5.11", "status": "unaffected", "versionType": "semver"}, {"version": "6.1.191", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.6.72", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.12.10", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver"}, {"version": "6.13", "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": "5.11", "versionEndExcluding": "6.1.191"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.6.72"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.12.10"}, {"vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "5.11", "versionEndExcluding": "6.13"}]}]}], "references": [{"url": "https://git.kernel.org/stable/c/1fb37b7840fdcbf69d062a79d14afbf566b11873"}, {"url": "https://git.kernel.org/stable/c/24b85a8b0310e0144da9ab30be42e87e6476638a"}, {"url": "https://git.kernel.org/stable/c/aee5f69f3e6cd82bfefaca1b70b40b6cd8f3f784"}, {"url": "https://git.kernel.org/stable/c/6aecd91a5c5b68939cf4169e32bc49f3cd2dd329"}], "title": "btrfs: avoid NULL pointer dereference if no valid extent tree", "x_generator": {"engine": "bippy-1.2.0"}}, "adp": [{"metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2025-21658", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2025-10-01T19:52:37.080379Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-476", "description": "CWE-476 NULL Pointer Dereference"}]}], "title": "CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-10-01T19:57:13.496Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 5.5, "attackVector": "LOCAL", "baseSeverity": "MEDIUM", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", "availabilityImpact": "HIGH", "privilegesRequired": "LOW", "confidentialityImpact": "NONE"}}, {"other": {"type": "ssvc", "content": {"id": "CVE-2025-21658", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "no"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2025-10-01T19:52:37.080379Z"}}}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-476", "description": "CWE-476 NULL Pointer Dereference"}]}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2025-10-01T15:58:02.174Z"}}], "cna": {"title": "btrfs: avoid NULL pointer dereference if no valid extent tree", "affected": [{"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "1fb37b7840fdcbf69d062a79d14afbf566b11873", "versionType": "git"}, {"status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "24b85a8b0310e0144da9ab30be42e87e6476638a", "versionType": "git"}, {"status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "aee5f69f3e6cd82bfefaca1b70b40b6cd8f3f784", "versionType": "git"}, {"status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "lessThan": "6aecd91a5c5b68939cf4169e32bc49f3cd2dd329", "versionType": "git"}], "programFiles": ["fs/btrfs/scrub.c"], "defaultStatus": "unaffected"}, {"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "product": "Linux", "versions": [{"status": "affected", "version": "5.11"}, {"status": "unaffected", "version": "0", "lessThan": "5.11", "versionType": "semver"}, {"status": "unaffected", "version": "6.1.191", "versionType": "semver", "lessThanOrEqual": "6.1.*"}, {"status": "unaffected", "version": "6.6.72", "versionType": "semver", "lessThanOrEqual": "6.6.*"}, {"status": "unaffected", "version": "6.12.10", "versionType": "semver", "lessThanOrEqual": "6.12.*"}, {"status": "unaffected", "version": "6.13", "versionType": "original_commit_for_fix", "lessThanOrEqual": "*"}], "programFiles": ["fs/btrfs/scrub.c"], "defaultStatus": "affected"}], "references": [{"url": "https://git.kernel.org/stable/c/1fb37b7840fdcbf69d062a79d14afbf566b11873"}, {"url": "https://git.kernel.org/stable/c/24b85a8b0310e0144da9ab30be42e87e6476638a"}, {"url": "https://git.kernel.org/stable/c/aee5f69f3e6cd82bfefaca1b70b40b6cd8f3f784"}, {"url": "https://git.kernel.org/stable/c/6aecd91a5c5b68939cf4169e32bc49f3cd2dd329"}], "x_generator": {"engine": "bippy-1.2.0"}, "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: avoid NULL pointer dereference if no valid extent tree\n\n[BUG]\nSyzbot reported a crash with the following call trace:\n\n BTRFS info (device loop0): scrub: started on devid 1\n BUG: kernel NULL pointer dereference, address: 0000000000000208\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0\n Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI\n CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206\n Tainted: [O]=OOT_MODULE\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022\n RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]\n Call Trace:\n <TASK>\n scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]\n scrub_simple_mirror+0x175/0x260 [btrfs]\n scrub_stripe+0x5d4/0x6c0 [btrfs]\n scrub_chunk+0xbb/0x170 [btrfs]\n scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]\n btrfs_scrub_dev+0x240/0x600 [btrfs]\n btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]\n ? do_sys_openat2+0xa5/0xf0\n __x64_sys_ioctl+0x97/0xc0\n do_syscall_64+0x4f/0x120\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n </TASK>\n\n[CAUSE]\nThe reproducer is using a corrupted image where extent tree root is\ncorrupted, thus forcing to use \"rescue=all,ro\" mount option to mount the\nimage.\n\nThen it triggered a scrub, but since scrub relies on extent tree to find\nwhere the data/metadata extents are, scrub_find_fill_first_stripe()\nrelies on an non-empty extent root.\n\nBut unfortunately scrub_find_fill_first_stripe() doesn't really expect\nan NULL pointer for extent root, it use extent_root to grab fs_info and\ntriggered a NULL pointer dereference.\n\n[FIX]\nAdd an extra check for a valid extent root at the beginning of\nscrub_find_fill_first_stripe().\n\nThe new error path is introduced by 42437a6386ff (\"btrfs: introduce\nmount option rescue=ignorebadroots\"), but that's pretty old, and later\ncommit b979547513ff (\"btrfs: scrub: introduce helper to find and fill\nsector info for a scrub_stripe\") changed how we do scrub.\n\nSo for kernels older than 6.6, the fix will need manual backport."}], "cpeApplicability": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.1.191", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.6.72", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.12.10", "versionStartIncluding": "5.11"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "versionEndExcluding": "6.13", "versionStartIncluding": "5.11"}], "operator": "OR"}]}], "providerMetadata": {"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-30T12:20:41.665Z"}}}, "cveMetadata": {"cveId": "CVE-2025-21658", "state": "PUBLISHED", "dateUpdated": "2026-10-30T12:20:41.665Z", "dateReserved": "2024-12-29T08:45:45.731Z", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "datePublished": "2025-01-21T12:18:14.578Z", "assignerShortName": "Linux"}, "dataVersion": "5.2"}

{"affected": [{"affectedData": [{"defaultStatus": "unaffected", "product": "Linux", "programFiles": ["fs/btrfs/scrub.c"], "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "vendor": "Linux", "versions": [{"lessThan": "1fb37b7840fdcbf69d062a79d14afbf566b11873", "status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "versionType": "git"}, {"lessThan": "24b85a8b0310e0144da9ab30be42e87e6476638a", "status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "versionType": "git"}, {"lessThan": "aee5f69f3e6cd82bfefaca1b70b40b6cd8f3f784", "status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "versionType": "git"}, {"lessThan": "6aecd91a5c5b68939cf4169e32bc49f3cd2dd329", "status": "affected", "version": "42437a6386ffeaaf200731e73d723ea491f3fe7d", "versionType": "git"}]}, {"defaultStatus": "affected", "product": "Linux", "programFiles": ["fs/btrfs/scrub.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": "6.1.*", "status": "unaffected", "version": "6.1.191", "versionType": "semver"}, {"lessThanOrEqual": "6.6.*", "status": "unaffected", "version": "6.6.72", "versionType": "semver"}, {"lessThanOrEqual": "6.12.*", "status": "unaffected", "version": "6.12.10", "versionType": "semver"}, {"lessThanOrEqual": "*", "status": "unaffected", "version": "6.13", "versionType": "original_commit_for_fix"}]}], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "AD41C3D4-D314-4BC5-888E-E1B87323349D", "versionEndExcluding": "6.6.72", "versionStartIncluding": "5.11", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "matchCriteriaId": "02D604F6-10D1-4F7B-A022-0888406A1121", "versionEndExcluding": "6.12.10", "versionStartIncluding": "6.7", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc1:*:*:*:*:*:*", "matchCriteriaId": "62567B3C-6CEE-46D0-BC2E-B3717FBF7D13", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc2:*:*:*:*:*:*", "matchCriteriaId": "5A073481-106D-4B15-B4C7-FB0213B8E1D4", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc3:*:*:*:*:*:*", "matchCriteriaId": "DE491969-75AE-4A6B-9A58-8FC5AF98798F", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc4:*:*:*:*:*:*", "matchCriteriaId": "93C0660D-7FB8-4FBA-892A-B064BA71E49E", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc5:*:*:*:*:*:*", "matchCriteriaId": "034C36A6-C481-41F3-AE9A-D116E5BE6895", "vulnerable": true}, {"criteria": "cpe:2.3:o:linux:linux_kernel:6.13:rc6:*:*:*:*:*:*", "matchCriteriaId": "8AF9DC49-2085-4FFB-A7E3-73DFAFECC7F2", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbtrfs: avoid NULL pointer dereference if no valid extent tree\n\n[BUG]\nSyzbot reported a crash with the following call trace:\n\n BTRFS info (device loop0): scrub: started on devid 1\n BUG: kernel NULL pointer dereference, address: 0000000000000208\n #PF: supervisor read access in kernel mode\n #PF: error_code(0x0000) - not-present page\n PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0\n Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI\n CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206\n Tainted: [O]=OOT_MODULE\n Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022\n RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]\n Call Trace:\n <TASK>\n scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]\n scrub_simple_mirror+0x175/0x260 [btrfs]\n scrub_stripe+0x5d4/0x6c0 [btrfs]\n scrub_chunk+0xbb/0x170 [btrfs]\n scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]\n btrfs_scrub_dev+0x240/0x600 [btrfs]\n btrfs_ioctl+0x1dc8/0x2fa0 [btrfs]\n ? do_sys_openat2+0xa5/0xf0\n __x64_sys_ioctl+0x97/0xc0\n do_syscall_64+0x4f/0x120\n entry_SYSCALL_64_after_hwframe+0x76/0x7e\n </TASK>\n\n[CAUSE]\nThe reproducer is using a corrupted image where extent tree root is\ncorrupted, thus forcing to use \"rescue=all,ro\" mount option to mount the\nimage.\n\nThen it triggered a scrub, but since scrub relies on extent tree to find\nwhere the data/metadata extents are, scrub_find_fill_first_stripe()\nrelies on an non-empty extent root.\n\nBut unfortunately scrub_find_fill_first_stripe() doesn't really expect\nan NULL pointer for extent root, it use extent_root to grab fs_info and\ntriggered a NULL pointer dereference.\n\n[FIX]\nAdd an extra check for a valid extent root at the beginning of\nscrub_find_fill_first_stripe().\n\nThe new error path is introduced by 42437a6386ff (\"btrfs: introduce\nmount option rescue=ignorebadroots\"), but that's pretty old, and later\ncommit b979547513ff (\"btrfs: scrub: introduce helper to find and fill\nsector info for a scrub_stripe\") changed how we do scrub.\n\nSo for kernels older than 6.6, the fix will need manual backport."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: btrfs: evitar la desreferencia de puntero NULL si no hay un \u00e1rbol de extensi\u00f3n v\u00e1lido [ERROR] Syzbot inform\u00f3 de un fallo con el siguiente seguimiento de llamada: Informaci\u00f3n de BTRFS (bucle de dispositivo 0): scrub: iniciado en devid 1 ERROR: desreferencia de puntero NULL del kernel, direcci\u00f3n: 0000000000000208 #PF: acceso de lectura de supervisor en modo kernel #PF: error_code(0x0000) - p\u00e1gina no presente PGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0 Oops: Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 1 UID: 0 PID: 689 Comm: repro Kdump: cargado Tainted: G O 6.13.0-rc4-custom+ #206 Tainted: [O]=OOT_MODULE Nombre de hardware: PC est\u00e1ndar QEMU (Q35 + ICH9, 2009), BIOS desconocido 02/02/2022 RIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs] Seguimiento de llamadas: Scrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs] Scrub_simple_mirror+0x175/0x260 [btrfs] Scrub_stripe+0x5d4/0x6c0 [btrfs] Scrub_chunk+0xbb/0x170 [btrfs] Scrub_enumerate_chunks+0x2f4/0x5f0 [btrfs] btrfs_scrub_dev+0x240/0x600 [btrfs] btrfs_ioctl+0x1dc8/0x2fa0 [btrfs] ? do_sys_openat2+0xa5/0xf0 __x64_sys_ioctl+0x97/0xc0 do_syscall_64+0x4f/0x120 entry_SYSCALL_64_after_hwframe+0x76/0x7e [CAUSA] El reproductor est\u00e1 usando una imagen da\u00f1ada donde la ra\u00edz del \u00e1rbol de extensi\u00f3n est\u00e1 da\u00f1ada, lo que obliga a usar la opci\u00f3n de montaje \"rescue=all,ro\" para montar la imagen. Luego, activ\u00f3 una limpieza, pero como la limpieza depende del \u00e1rbol de extensi\u00f3n para encontrar d\u00f3nde est\u00e1n las extensiones de datos/metadatos, scrub_find_fill_first_stripe() depende de una ra\u00edz de extensi\u00f3n no vac\u00eda. Pero desafortunadamente scrub_find_fill_first_stripe() no espera realmente un puntero NULL para la ra\u00edz de la extensi\u00f3n, usa extended_root para obtener fs_info y activa una desreferencia de puntero NULL. [SOLUCI\u00d3N] Agregue una verificaci\u00f3n adicional para una ra\u00edz de extensi\u00f3n v\u00e1lida al comienzo de scrub_find_fill_first_stripe(). La nueva ruta de error es introducida por 42437a6386ff (\"btrfs: introduce mount option rescue=ignorebadroots\"), pero eso es bastante antiguo, y el commit posterior b979547513ff (\"btrfs: scrub: introduce helper to find and fill sector info for a scrub_stripe\") cambi\u00f3 la forma en que realizamos el scrub. Entonces, para los kernels anteriores a 6.6, la soluci\u00f3n necesitar\u00e1 una adaptaci\u00f3n manual. "}], "id": "CVE-2025-21658", "lastModified": "2026-10-30T13:17:51.060", "metrics": {"cvssMetricV31": [{"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}, {"cvssData": {"attackComplexity": "LOW", "attackVector": "LOCAL", "availabilityImpact": "HIGH", "baseScore": 5.5, "baseSeverity": "MEDIUM", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "privilegesRequired": "LOW", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "version": "3.1"}, "exploitabilityScore": 1.8, "impactScore": 3.6, "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}], "ssvcV203": [{"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "ssvcData": {"id": "CVE-2025-21658", "options": [{"exploitation": "none"}, {"automatable": "no"}, {"technicalImpact": "partial"}], "role": "CISA Coordinator", "timestamp": "2025-10-01T19:52:37.080379Z", "version": "2.0.3"}}]}, "published": "2025-01-21T13:15:09.437", "references": [{"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "url": "https://git.kernel.org/stable/c/1fb37b7840fdcbf69d062a79d14afbf566b11873"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/24b85a8b0310e0144da9ab30be42e87e6476638a"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/6aecd91a5c5b68939cf4169e32bc49f3cd2dd329"}, {"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "tags": ["Patch"], "url": "https://git.kernel.org/stable/c/aee5f69f3e6cd82bfefaca1b70b40b6cd8f3f784"}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-476"}], "source": "nvd@nist.gov", "type": "Primary"}, {"description": [{"lang": "en", "value": "CWE-476"}], "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "type": "Secondary"}]}

{"bugzilla": {"description": "kernel: btrfs: avoid NULL pointer dereference if no valid extent tree", "id": "2339123", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2339123"}, "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-476", "details": ["In the Linux kernel, the following vulnerability has been resolved:\nbtrfs: avoid NULL pointer dereference if no valid extent tree\n[BUG]\nSyzbot reported a crash with the following call trace:\nBTRFS info (device loop0): scrub: started on devid 1\nBUG: kernel NULL pointer dereference, address: 0000000000000208\n#PF: supervisor read access in kernel mode\n#PF: error_code(0x0000) - not-present page\nPGD 106e70067 P4D 106e70067 PUD 107143067 PMD 0\nOops: Oops: 0000 [#1] PREEMPT SMP NOPTI\nCPU: 1 UID: 0 PID: 689 Comm: repro Kdump: loaded Tainted: G O 6.13.0-rc4-custom+ #206\nTainted: [O]=OOT_MODULE\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS unknown 02/02/2022\nRIP: 0010:find_first_extent_item+0x26/0x1f0 [btrfs]\nCall Trace:\n<TASK>\nscrub_find_fill_first_stripe+0x13d/0x3b0 [btrfs]\nscrub_simple_mirror+0x175/0x260 [btrfs]\nscrub_stripe+0x5d4/0x6c0 [btrfs]\nscrub_chunk+0xbb/0x170 [btrfs]\nscrub_enumerate_chunks+0x2f4/0x5f0 [btrfs]\nbtrfs_scrub_dev+0x240/0x600 [btrfs]\nbtrfs_ioctl+0x1dc8/0x2fa0 [btrfs]\n? do_sys_openat2+0xa5/0xf0\n__x64_sys_ioctl+0x97/0xc0\ndo_syscall_64+0x4f/0x120\nentry_SYSCALL_64_after_hwframe+0x76/0x7e\n</TASK>\n[CAUSE]\nThe reproducer is using a corrupted image where extent tree root is\ncorrupted, thus forcing to use \"rescue=all,ro\" mount option to mount the\nimage.\nThen it triggered a scrub, but since scrub relies on extent tree to find\nwhere the data/metadata extents are, scrub_find_fill_first_stripe()\nrelies on an non-empty extent root.\nBut unfortunately scrub_find_fill_first_stripe() doesn't really expect\nan NULL pointer for extent root, it use extent_root to grab fs_info and\ntriggered a NULL pointer dereference.\n[FIX]\nAdd an extra check for a valid extent root at the beginning of\nscrub_find_fill_first_stripe().\nThe new error path is introduced by 42437a6386ff (\"btrfs: introduce\nmount option rescue=ignorebadroots\"), but that's pretty old, and later\ncommit b979547513ff (\"btrfs: scrub: introduce helper to find and fill\nsector info for a scrub_stripe\") changed how we do scrub.\nSo for kernels older than 6.6, the fix will need manual backport."], "name": "CVE-2025-21658", "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": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 6"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "package_name": "kernel", "product_name": "Red Hat Enterprise Linux 7"}, {"cpe": "cpe:/o:redhat:enterprise_linux:7", "fix_state": "Out of support scope", "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": "2025-01-21T00:00:00Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2025-21658\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-21658\nhttps://lore.kernel.org/linux-cve-announce/2025012132-CVE-2025-21658-78d9@gregkh/T"], "threat_severity": "Moderate"}

{}