{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-97608", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-09-24T16:01:01.158Z", "datePublished": "2026-09-25T10:22:19.030Z", "dateUpdated": "2026-10-19T09:10:12.020Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-10-19T09:10:12.020Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_log: unregister loggers before per-net teardown\n\nnf_log_syslog and nfnetlink_log unregister their per-network namespace\noperations before unregistering their global logger backends. This\nleaves a window where a sysctl or netlink writer can rebind the still-\nregistered logger after the per-net pre-exit callback cleared the old\nselection.\n\nThe race looks like this:\n\n CPU 0 CPU 1\n ---- ----\n unregister_pernet_subsys()\n nf_log_unset(net, logger)\n net->nf.nf_loggers[pf] = NULL\n\n lock nf_log_mutex\n find logger in loggers[][]\n net->nf.nf_loggers[pf] = logger\n unlock nf_log_mutex\n\n nf_log_unregister(logger)\n lock nf_log_mutex\n loggers[pf][type] = NULL\n unlock nf_log_mutex\n synchronize_rcu()\n module exit returns\n module core frees backend memory\n\nLater, a sysctl read or packet logging operation can dereference the\nstale per-net logger pointer.\n\nFix this by unregistering the global logger backends before tearing down\nper-net state. Once the global registrations are gone, later writers can\nno longer rebind the logger. unregister_pernet_subsys() already waits\nfor an RCU grace period after the pre-exit callback clears the per-net\nselection, while nf_log_unregister() continues to cover readers of the\nglobal logger table.\n\nApply this ordering fix to both nf_log backends that combine per-net\nteardown with global logger registration." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H", "baseScore": 7, "baseSeverity": "HIGH" }, "scenarios": [ { "lang": "en", "value": "AV:L - Both sides of the race are local. One is module exit (nf_log_syslog_exit or nfnetlink_log_fini through delete_module). The other is a write to the net.netfilter.nf_log. sysctl, handled by nf_log_proc_dostring(), or an NFULNL_CFG_CMD_PF_BIND message over nfnetlink. No remote peer supplies anything that causes the stale nf_loggers[] pointer.\nAC:H - The attacker controls the rebind side, but the other side is a module unload that needs init-namespace CAP_SYS_MODULE. The attacker cannot make it happen. They must win the short window between nf_log_unset() in the per-net pre-exit and nf_log_unregister() while an admin unloads the module.\nPR:L - nf_log_proc_dostring() rebinds net->nf.nf_loggers[pf] from the per-netns sysctl, which is writable in a non-init netns. The nfnetlink PF_BIND path only checks netlink_net_capable(CAP_NET_ADMIN). So user namespaces (unshare -Urn) are enough for the attacker's side.\nUI:N - No victim action on attacker-supplied content is needed. The module unload is an admin action outside the attacker's control and is already counted under AC:H.\nS:U - The stale logger pointer is used inside the same kernel. Nothing crosses a VM, IOMMU or other security boundary.\nC:H - After the module is freed, a sysctl read dereferences logger->name, and nf_log_packet() calls logger->logfn through the dangling nf_loggers[pf] pointer. This is a use-after-free of freed module memory that can be leveraged to disclose kernel memory.\nI:H - nf_log_packet() makes an indirect call through logger->logfn in the freed module's memory. If that memory is reused, this gives control-flow hijacking and memory corruption.\nA:H - Logging a packet, or reading the sysctl, after the logger module is gone faults on the unmapped or reused module memory and oopses the kernel." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/netfilter/nf_log_syslog.c", "net/netfilter/nfnetlink_log.c" ], "versions": [ { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "51417230716b73f6aa1dc402b3a56d3382a694dc", "status": "affected", "versionType": "git" }, { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "b0514ca1ee6f2b708d6c602ea946acdfc6a90e24", "status": "affected", "versionType": "git" }, { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "90166834b7dc6131aa42b6b14b8b4ed47be97079", "status": "affected", "versionType": "git" }, { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "eaec35fae8f2052c1878a5c7cc7699d8357d79f2", "status": "affected", "versionType": "git" }, { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "64803ba0a05791cf9ca874466480e4c4cadaf7ab", "status": "affected", "versionType": "git" }, { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "dce24f3a146948595bb1b86347f31e20b4975daa", "status": "affected", "versionType": "git" }, { "version": "5b023fc8d8e0997e0b7ea6506d243afd5478c96e", "lessThan": "2c018cc4842c33f0c732962e2ab58635e8ae5823", "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/netfilter/nf_log_syslog.c", "net/netfilter/nfnetlink_log.c" ], "versions": [ { "version": "3.10", "status": "affected" }, { "version": "0", "lessThan": "3.10", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.222", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.189", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.158", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.111", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.53", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.2.7", "lessThanOrEqual": "7.2.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.3", "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": "3.10", "versionEndExcluding": "5.15.222" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.1.189" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.6.158" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.12.111" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.18.53" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.2.7" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.3" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/51417230716b73f6aa1dc402b3a56d3382a694dc" }, { "url": "https://git.kernel.org/stable/c/b0514ca1ee6f2b708d6c602ea946acdfc6a90e24" }, { "url": "https://git.kernel.org/stable/c/90166834b7dc6131aa42b6b14b8b4ed47be97079" }, { "url": "https://git.kernel.org/stable/c/eaec35fae8f2052c1878a5c7cc7699d8357d79f2" }, { "url": "https://git.kernel.org/stable/c/64803ba0a05791cf9ca874466480e4c4cadaf7ab" }, { "url": "https://git.kernel.org/stable/c/dce24f3a146948595bb1b86347f31e20b4975daa" }, { "url": "https://git.kernel.org/stable/c/2c018cc4842c33f0c732962e2ab58635e8ae5823" } ], "title": "netfilter: nf_log: unregister loggers before per-net teardown", "x_generator": { "engine": "bippy-1.2.0" } } } }