CVE-2024-42109

{"id": "CVE-2024-42109", "cveTags": [], "metrics": {"cvssMetricV31": [{"type": "Primary", "source": "nvd@nist.gov", "cvssData": {"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"}, "impactScore": 3.6, "exploitabilityScore": 1.8}]}, "published": "2024-07-30T08:15:03.407", "references": [{"url": "https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}, {"url": "https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0", "tags": ["Patch"], "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}], "vulnStatus": "Analyzed", "weaknesses": [{"type": "Primary", "source": "nvd@nist.gov", "description": [{"lang": "en", "value": "NVD-CWE-noinfo"}]}], "descriptions": [{"lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: unconditionally flush pending work before notifier\n\nsyzbot reports:\n\nKASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831\nKASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530\nKASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597\nRead of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45\n[..]\nWorkqueue: events nf_tables_trans_destroy_work\nCall Trace:\n nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline]\n nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline]\n nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597\n\nProblem is that the notifier does a conditional flush, but its possible\nthat the table-to-be-removed is still referenced by transactions being\nprocessed by the worker, so we need to flush unconditionally.\n\nWe could make the flush_work depend on whether we found a table to delete\nin nf-next to avoid the flush for most cases.\n\nAFAICS this problem is only exposed in nf-next, with\ncommit e169285f8c56 (\"netfilter: nf_tables: do not store nft_ctx in transaction objects\"),\nwith this commit applied there is an unconditional fetch of\ntable->family which is whats triggering the above splat."}, {"lang": "es", "value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nf_tables: vaciar incondicionalmente el trabajo pendiente antes de que el notificador syzbot informe: KASAN: slab-uaf en nft_ctx_update include/net/netfilter/nf_tables.h:1831 KASAN: slab-uaf en nft_commit_release net/netfilter/nf_tables_api.c:9530 KASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Lectura de tama\u00f1o 2 en la direcci\u00f3n ffff88802b0051c4 por tarea kworker/1:1/45 [..] ue : eventos nf_tables_trans_destroy_work Seguimiento de llamadas: nft_ctx_update include/net/netfilter/nf_tables.h:1831 [en l\u00ednea] nft_commit_release net/netfilter/nf_tables_api.c:9530 [en l\u00ednea] nf_tables_trans_destroy_work+0x152b/0x1750 s_api.c:9597 El problema es que el notificador realiza un vaciado condicional, pero es posible que las transacciones que procesa el trabajador a\u00fan hagan referencia a la tabla que se va a eliminar, por lo que debemos realizar un vaciado incondicional. Podr\u00edamos hacer que flux_work dependa de si encontramos una tabla para eliminar en nf-next para evitar el vaciado en la mayor\u00eda de los casos. AFAICS, este problema solo se expone en nf-next, con la confirmaci\u00f3n e169285f8c56 (\"netfilter: nf_tables: no almacenar nft_ctx en objetos de transacci\u00f3n\"), con esta confirmaci\u00f3n aplicada hay una b\u00fasqueda incondicional de tabla->familia que es lo que desencadena lo anterior salpicar."}], "lastModified": "2024-08-27T13:44:00.143", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "5FD25434-47C3-45B8-B46A-6352379CD2F9", "versionEndExcluding": "5.15.163", "versionStartIncluding": "5.15.129"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "24E84470-CB41-4B10-ACC2-6579459F3A48", "versionEndExcluding": "6.1.98", "versionStartIncluding": "6.1.50"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "E079242F-1B25-40DA-BCE2-2A7965C9168E", "versionEndExcluding": "6.6.39", "versionStartIncluding": "6.5"}, {"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "ADCC1407-0CB3-4C8F-B4C5-07F682CD7085", "versionEndExcluding": "6.9.9", "versionStartIncluding": "6.7"}], "operator": "OR"}]}], "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"}