{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-74660", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-15T05:44:03.924Z", "datePublished": "2026-08-22T15:32:33.677Z", "dateUpdated": "2026-08-22T15:32:33.677Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-22T15:32:33.677Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: ebt_nflog: pin the NFLOG backend\n\nnf_log_unregister() runs after the per-net teardown so its final RCU\ngrace period also drains readers that obtained the logger from a per-net\nbinding. However, ebt_nflog passes an explicit ULOG log type to\nnf_log_packet() without holding a reference on the selected logger module,\nunlike the xt_NFLOG and nft_log frontends.\n\nAn ebtables nflog rule can therefore remain callable while nfnetlink_log\nis unloaded. The resulting interleaving is:\n\n CPU 0 CPU 1\n nfnetlink_log_fini()\n unregister_pernet_subsys()\n kfree(nfnl_log_pernet(net))\n ebt_nflog_tg()\n nf_log_packet()\n nfulnl_log_packet()\n instance_lookup_get_rcu()\n\nThe global ULOG logger is still registered at this point, so CPU 1\ndereferences the per-net state after CPU 0 has freed it. KASAN reported:\n\n BUG: KASAN: slab-use-after-free in instance_lookup_get_rcu\n Read of size 8 at addr ff110001052e6210 by task poc/92\n Call Trace:\n instance_lookup_get_rcu+0x1ce/0x1f0 [nfnetlink_log]\n nfulnl_log_packet+0x248/0x2fb0 [nfnetlink_log]\n nf_log_packet+0x204/0x300\n ebt_nflog_tg+0x351/0x550\n ebt_do_table+0xedf/0x22b0\n Allocated by task 90:\n __kmalloc_noprof+0x186/0x470\n ops_init+0x6d/0x420\n register_pernet_operations+0x2f6/0x670\n register_pernet_subsys+0x23/0x40\n Freed by task 93:\n kfree+0x131/0x3c0\n ops_undo_list+0x3e3/0x700\n unregister_pernet_operations+0x232/0x490\n unregister_pernet_subsys+0x1c/0x30\n nfnetlink_log_fini+0x34/0x450 [nfnetlink_log]\n\nAcquire the ULOG logger module reference when an ebt_nflog rule is\nvalidated and release it when the rule is destroyed. Request the NFLOG\nbackend for legacy callers when needed, matching xt_NFLOG. This prevents\nmodule teardown until all ebt_nflog rules have stopped using the logger." } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/bridge/netfilter/ebt_nflog.c" ], "versions": [ { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "3bcce49d617c593c7606083bfdb464a1761fa68d", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "394d7939c6b2b9e6bea0844c89efb5913168d898", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "2cac4294f184c9bc19ff82552c62b80498694c39", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "9d8a94b48b393885e7f876c8ef68ed4da5012078", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "6809379a860b9fccbb5435bf08343f6d081ac68d", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "47a119ec8a7e2d5c8c4e86fb1a56c4e696e500fb", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "e2ab7e878bdbe80104c879c31fd2d82a476703b8", "status": "affected", "versionType": "git" }, { "version": "c83fa19603bdaeef17b815713dbbe3230c8a34ee", "lessThan": "30825970339c107bacaf7f61af90fcdb1f597ca1", "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/netfilter/ebt_nflog.c" ], "versions": [ { "version": "4.12", "status": "affected" }, { "version": "0", "lessThan": "4.12", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "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": "4.12", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.6.152" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.12.104" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "6.18.45" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "7.1.9" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.12", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/3bcce49d617c593c7606083bfdb464a1761fa68d" }, { "url": "https://git.kernel.org/stable/c/394d7939c6b2b9e6bea0844c89efb5913168d898" }, { "url": "https://git.kernel.org/stable/c/2cac4294f184c9bc19ff82552c62b80498694c39" }, { "url": "https://git.kernel.org/stable/c/9d8a94b48b393885e7f876c8ef68ed4da5012078" }, { "url": "https://git.kernel.org/stable/c/6809379a860b9fccbb5435bf08343f6d081ac68d" }, { "url": "https://git.kernel.org/stable/c/47a119ec8a7e2d5c8c4e86fb1a56c4e696e500fb" }, { "url": "https://git.kernel.org/stable/c/e2ab7e878bdbe80104c879c31fd2d82a476703b8" }, { "url": "https://git.kernel.org/stable/c/30825970339c107bacaf7f61af90fcdb1f597ca1" } ], "title": "netfilter: ebt_nflog: pin the NFLOG backend", "x_generator": { "engine": "bippy-1.2.0" } } } }