{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-45859","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-05-13T15:03:33.079Z","datePublished":"2026-05-27T12:15:39.322Z","dateUpdated":"2026-05-30T10:45:35.721Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-05-30T10:45:35.721Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation\n\nUlrich reports a regression with nfqueue:\n\nIf an application did not set the 'F_GSO' capability flag and a gso\npacket with an unconfirmed nf_conn entry is received all packets are\nnow dropped instead of queued, because the check happens after\nskb_gso_segment().  In that case, we did have exclusive ownership\nof the skb and its associated conntrack entry.  The elevated use\ncount is due to skb_clone happening via skb_gso_segment().\n\nMove the check so that its peformed vs. the aggregated packet.\n\nThen, annotate the individual segments except the first one so we\ncan do a 2nd check at reinject time.\n\nFor the normal case, where userspace does in-order reinjects, this avoids\npacket drops: first reinjected segment continues traversal and confirms\nentry, remaining segments observe the confirmed entry.\n\nWhile at it, simplify nf_ct_drop_unconfirmed(): We only care about\nunconfirmed entries with a refcnt > 1, there is no need to special-case\ndying entries.\n\nThis only happens with UDP.  With TCP, the only unconfirmed packet will\nbe the TCP SYN, those aren't aggregated by GRO.\n\nNext patch adds a udpgro test case to cover this scenario."}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","baseScore":7.5,"baseSeverity":"HIGH"}}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/netfilter/nf_queue.h","net/netfilter/nfnetlink_queue.c"],"versions":[{"version":"7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb","lessThan":"79b713ef4261a8ead96af4703f89d0b5f25532e2","status":"affected","versionType":"git"},{"version":"7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb","lessThan":"23901aa6b8a2f294c4b774436b4691f3ff863a8f","status":"affected","versionType":"git"},{"version":"7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb","lessThan":"b740e7ddd7ca0dbfeafca3f5e52717206cf28524","status":"affected","versionType":"git"},{"version":"7d8dc1c7be8d3509e8f5164dd5df64c8e34d7eeb","lessThan":"207b3ebacb6113acaaec0d171d5307032c690004","status":"affected","versionType":"git"},{"version":"6c4a0ba674f410ab99a30a16f32dac0ebfed5cd3","status":"affected","versionType":"git"},{"version":"6dcc8ba8a6074bb79040f502dc66ad23a58a1c86","status":"affected","versionType":"git"},{"version":"74e6eb7fd27ef1ccc68041dbc66e6d80d2e4a1a0","status":"affected","versionType":"git"},{"version":"025b3326c5c409b372d0103ad30f174e55adbd1b","status":"affected","versionType":"git"},{"version":"5.15.166","lessThan":"5.16","status":"affected","versionType":"semver"},{"version":"6.1.107","lessThan":"6.2","status":"affected","versionType":"semver"},{"version":"6.6.48","lessThan":"6.7","status":"affected","versionType":"semver"},{"version":"6.10.7","lessThan":"6.11","status":"affected","versionType":"semver"}]},{"product":"Linux","vendor":"Linux","defaultStatus":"affected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["include/net/netfilter/nf_queue.h","net/netfilter/nfnetlink_queue.c"],"versions":[{"version":"6.11","status":"affected"},{"version":"0","lessThan":"6.11","status":"unaffected","versionType":"semver"},{"version":"6.12.75","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.14","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"6.19.4","lessThanOrEqual":"6.19.*","status":"unaffected","versionType":"semver"},{"version":"7.0","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":"6.11","versionEndExcluding":"6.12.75"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.18.14"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"6.19.4"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.11","versionEndExcluding":"7.0"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.15.166"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.1.107"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.6.48"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"6.10.7"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/79b713ef4261a8ead96af4703f89d0b5f25532e2"},{"url":"https://git.kernel.org/stable/c/23901aa6b8a2f294c4b774436b4691f3ff863a8f"},{"url":"https://git.kernel.org/stable/c/b740e7ddd7ca0dbfeafca3f5e52717206cf28524"},{"url":"https://git.kernel.org/stable/c/207b3ebacb6113acaaec0d171d5307032c690004"}],"title":"netfilter: nfnetlink_queue: do shared-unconfirmed check before segmentation","x_generator":{"engine":"bippy-1.2.0"}}}}