{"api_version":"1","generated_at":"2026-09-25T12:39:47+00:00","cve":"CVE-2026-93288","urls":{"html":"https://cve.report/CVE-2026-93288","api":"https://cve.report/api/cve/CVE-2026-93288.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-93288","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-93288"},"summary":{"title":"netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state\n\nsashiko reports: \"nfnl_log_net_exit() calls nf_log_unset(), which\nclears the logger pointer without an RCU grace period.  Immediately after,\nops_free_list() frees the per-net state while concurrent packets might\nstill be executing nf_log_packet() under rcu_read_lock().\"\n\nClear the pointer via .pre_exit to make sure rcu readers have completed\nbefore pernet storage is free'd.  The change in nf_log_syslog.c is only\ndone for consistency: it doesn't use pernet data.","state":"PUBLISHED","assigner":"Linux","published_at":"2026-09-24 17:17:10","updated_at":"2026-09-25 05:17:02"},"problem_types":[],"metrics":[{"version":"3.1","source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"}},{"version":"3.1","source":"CNA","type":"DECLARED","score":"7.8","severity":"HIGH","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","data":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"}}],"references":[{"url":"https://git.kernel.org/stable/c/f4461654374576e9d5d0245fd534c46ad8509051","name":"https://git.kernel.org/stable/c/f4461654374576e9d5d0245fd534c46ad8509051","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/33d1469b0124cc0baaea7a2032123b77a81e0940","name":"https://git.kernel.org/stable/c/33d1469b0124cc0baaea7a2032123b77a81e0940","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://git.kernel.org/stable/c/dc20050b6b12ca58066715d088e1a537535d938d","name":"https://git.kernel.org/stable/c/dc20050b6b12ca58066715d088e1a537535d938d","refsource":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","tags":[],"title":"","mime":"","httpstatus":"","archivestatus":"0"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-93288","name":"CVE Program record","refsource":"CVE.ORG","tags":["canonical"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-93288","name":"NVD vulnerability detail","refsource":"NVD","tags":["canonical","analysis"]}],"affected":[{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 f4461654374576e9d5d0245fd534c46ad8509051 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 dc20050b6b12ca58066715d088e1a537535d938d git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 33d1469b0124cc0baaea7a2032123b77a81e0940 git","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.12.111 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"affected 6.18.53 semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.12.111 6.12.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 6.18.53 6.18.* semver","platforms":[]},{"source":"CNA","vendor":"Linux","product":"Linux","version":"unaffected 7.2 * original_commit_for_fix","platforms":[]}],"timeline":[],"solutions":[],"workarounds":[],"exploits":[],"credits":[],"nvd_cpes":[],"vendor_comments":[],"enrichments":{"kev":null,"epss":null,"legacy_qids":[]},"source_records":{"cve_program":{"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"Linux","programFiles":["net/netfilter/nf_log_syslog.c","net/netfilter/nfnetlink_log.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThan":"f4461654374576e9d5d0245fd534c46ad8509051","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"dc20050b6b12ca58066715d088e1a537535d938d","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"33d1469b0124cc0baaea7a2032123b77a81e0940","status":"affected","version":"1da177e4c3f41524e886b7f1b8a0c1fc7321cac2","versionType":"git"},{"lessThan":"6.12.111","status":"affected","version":"0","versionType":"semver"},{"lessThan":"6.18.53","status":"affected","version":"0","versionType":"semver"}]},{"defaultStatus":"affected","product":"Linux","programFiles":["net/netfilter/nf_log_syslog.c","net/netfilter/nfnetlink_log.c"],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","vendor":"Linux","versions":[{"lessThanOrEqual":"6.12.*","status":"unaffected","version":"6.12.111","versionType":"semver"},{"lessThanOrEqual":"6.18.*","status":"unaffected","version":"6.18.53","versionType":"semver"},{"lessThanOrEqual":"*","status":"unaffected","version":"7.2","versionType":"original_commit_for_fix"}]}],"cpeApplicability":[{"nodes":[{"cpeMatch":[{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.12.111","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"6.18.53","vulnerable":true},{"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionEndExcluding":"7.2","vulnerable":true}],"negate":false,"operator":"OR"}]}],"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state\n\nsashiko reports: \"nfnl_log_net_exit() calls nf_log_unset(), which\nclears the logger pointer without an RCU grace period.  Immediately after,\nops_free_list() frees the per-net state while concurrent packets might\nstill be executing nf_log_packet() under rcu_read_lock().\"\n\nClear the pointer via .pre_exit to make sure rcu readers have completed\nbefore pernet storage is free'd.  The change in nf_log_syslog.c is only\ndone for consistency: it doesn't use pernet data."}],"metrics":[{"cvssV3_1":{"baseScore":7.8,"baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","version":"3.1"},"scenarios":[{"lang":"en","value":"AV:L - The UAF is in nfnl_log_net_exit() (unset moved to nfnl_log_net_pre_exit): cleanup_net() frees nfnl_log_net via ops_free_list() while nf_log_packet()→nfulnl_log_packet() still uses nfnl_log_pernet(). Setup is local NETLINK_NETFILTER nfulnl_recv_config (NFULNL_CFG_CMD_PF_BIND); no remote protocol message carries the bug.\nAC:L - The attacker PF_BINDs nfulnl_logger through nfulnl_recv_config, generates packets that enter nf_log_packet() (conntrack nf_l4proto_log_invalid() while those hooks still exist, or NFLOG), and drops the netns so cleanup_net() races nfnl_log_net_exit()/ops_free_list() against that reader; both sides are attacker-controlled.\nPR:L - nfnetlink_rcv() requires CAP_NET_ADMIN via netlink_net_capable() in sock_net(skb->sk)->user_ns before nfulnl_recv_config can bind the logger; an unprivileged user obtains that capability in a user+net namespace (unshare -Urn).\nUI:N - The attacker issues nfulnl_recv_config, injects the logged packets, and destroys their own netns; no victim mount, file open, or other interaction is required.\nS:U - The slab UAF of struct nfnl_log_net inside nfulnl_log_packet()/instance_lookup_get_rcu() is host-kernel memory corruption in the same kernel authority, not a VM escape or IOMMU/DMA bypass.\nC:H - After ops_free_list() kfree()s the per-net object, nfulnl_log_packet() still calls nfnl_log_pernet() and instance_lookup_get_rcu() walks the freed instance_table hlist, a slab UAF that can be reclaimed for arbitrary kernel reads.\nI:H - Use-after-free of nfnl_log_net's instance_table and the resulting nfulnl_instance pointer chase (hlist, inst->lock, inst->skb) is a heap UAF write primitive that can hijack control flow.\nA:H - instance_lookup_get_rcu()/nfulnl_log_packet() dereferencing the freed nfnl_log_net can oops or panic the kernel even when the UAF is not turned into a full exploit."}]}],"providerMetadata":{"dateUpdated":"2026-09-25T05:10:02.962Z","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux"},"references":[{"url":"https://git.kernel.org/stable/c/f4461654374576e9d5d0245fd534c46ad8509051"},{"url":"https://git.kernel.org/stable/c/dc20050b6b12ca58066715d088e1a537535d938d"},{"url":"https://git.kernel.org/stable/c/33d1469b0124cc0baaea7a2032123b77a81e0940"}],"title":"netfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state","x_generator":{"engine":"bippy-1.2.0"}}},"cveMetadata":{"assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","assignerShortName":"Linux","cveId":"CVE-2026-93288","datePublished":"2026-09-24T16:02:12.144Z","dateReserved":"2026-09-17T16:02:15.099Z","dateUpdated":"2026-09-25T05:10:02.962Z","state":"PUBLISHED"},"dataType":"CVE_RECORD","dataVersion":"5.2"},"nvd":{"publishedDate":"2026-09-24 17:17:10","lastModifiedDate":"2026-09-25 05:17:02","problem_types":[],"metrics":{"cvssMetricV31":[{"source":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","baseScore":7.8,"baseSeverity":"HIGH","attackVector":"LOCAL","attackComplexity":"LOW","privilegesRequired":"LOW","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"HIGH","integrityImpact":"HIGH","availabilityImpact":"HIGH"},"exploitabilityScore":1.8,"impactScore":5.9}]},"configurations":[]},"legacy_mitre":{"record":{"CveYear":"2026","CveId":"93288","Ordinal":"1","Title":"netfilter: nfnetlink_log: wait for rcu grace period before freei","CVE":"CVE-2026-93288","Year":"2026"},"notes":[{"CveYear":"2026","CveId":"93288","Ordinal":"1","NoteData":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_log: wait for rcu grace period before freeing pernet state\n\nsashiko reports: \"nfnl_log_net_exit() calls nf_log_unset(), which\nclears the logger pointer without an RCU grace period.  Immediately after,\nops_free_list() frees the per-net state while concurrent packets might\nstill be executing nf_log_packet() under rcu_read_lock().\"\n\nClear the pointer via .pre_exit to make sure rcu readers have completed\nbefore pernet storage is free'd.  The change in nf_log_syslog.c is only\ndone for consistency: it doesn't use pernet data.","Type":"Description","Title":"netfilter: nfnetlink_log: wait for rcu grace period before freei"}]}}}