{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-72253","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","state":"PUBLISHED","assignerShortName":"Linux","dateReserved":"2026-08-09T03:40:39.915Z","datePublished":"2026-08-15T05:54:41.490Z","dateUpdated":"2026-08-23T12:47:08.038Z"},"containers":{"cna":{"providerMetadata":{"orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","shortName":"Linux","dateUpdated":"2026-08-23T12:47:08.038Z"},"descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_conntrack_sip: validate skb_dst() before accessing it\n\ntc ingress and openvswitch do not guarantee routing information to be\navailable. These subsystems use the conntrack helper infrastructure, and\nthe SIP helper relies on the skb_dst() to be present if\nsip_external_media is set to 1 (which is disabled by default as a module\nparameter).\n\nThis effectively disables the sip_external_media toggle for these\nsubsystems without resulting in a crash."}],"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"},"scenarios":[{"lang":"en","value":"AV:N - Remote attackers reach set_expected_rtp_rtcp() by sending crafted SIP/SDP (e.g., INVITE) through Open vSwitch or tc ingress ct(helper=sip) on internet-facing VoIP SBC/NFV gateways where packets are conntrack-processed before skb_dst routing metadata is attached.\nAC:L - Once sip_external_media=1, sip_direct_media=0, and the SIP helper are configured on OVS/tc ingress, the attacker fully controls SIP/SDP contents to reach the skb_dst(skb)->dev dereference without races or conditions outside their control.\nPR:N - Exploitation requires no privileges on the victim host; a remote SIP peer only needs to deliver malicious signaling to an already-configured OVS/tc SIP ALG with sip_external_media enabled, with no authentication or local access.\nUI:N - No victim user interaction is required; the kernel SIP helper parses attacker-supplied SIP/SDP during conntrack processing in softirq without any user action beyond normal automated packet handling.\nS:U - A NULL pointer dereference in nf_conntrack_sip causes a kernel oops/panic within the same kernel security domain on the gateway; it does not cross VM, IOMMU, or sandbox boundaries.\nC:N - The failure is a direct NULL pointer dereference from skb_dst(skb) being NULL on tc/OVS ingress paths; there is no use-after-free, out-of-bounds read, or other memory disclosure primitive.\nI:N - Accessing skb_dst(skb)->dev when skb_dst is NULL cannot modify memory or hijack control flow beyond the immediate fault; CVSS guidance assigns None for pure NULL-deref crashes without write capability.\nA:H - The invalid skb_dst dereference in set_expected_rtp_rtcp() during SIP SDP processing causes a kernel oops/panic-class fault, denying availability on the VoIP gateway until reboot; the crash is reliably reproducible with crafted SIP traffic."}]}],"affected":[{"product":"Linux","vendor":"Linux","defaultStatus":"unaffected","repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/netfilter/nf_conntrack_sip.c"],"versions":[{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"7866116a040b3a23fb094e7d8f7ea3d61b3ac70b","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"c5ef7228be04518d95591fc5369a9c554b19756d","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"0aec339694a56e263d4b22475ff7211d40900830","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"e64a48c50a1ff565a98c6a98d82b5b942868e76e","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"c199ed687c00841daf60e9d131976958583a8c09","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"09755dc62b026076b1d47f83489eb0547c8135e0","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"b843a96252f672332837ea2ecb7c8db0acf68e20","status":"affected","versionType":"git"},{"version":"cae3a2627520c3795b54533c5328b77af3405dbe","lessThan":"e5e24a365a5e024efef63cc49abb345fbd4852c5","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_conntrack_sip.c"],"versions":[{"version":"4.3","status":"affected"},{"version":"0","lessThan":"4.3","status":"unaffected","versionType":"semver"},{"version":"5.10.266","lessThanOrEqual":"5.10.*","status":"unaffected","versionType":"semver"},{"version":"5.15.217","lessThanOrEqual":"5.15.*","status":"unaffected","versionType":"semver"},{"version":"6.1.184","lessThanOrEqual":"6.1.*","status":"unaffected","versionType":"semver"},{"version":"6.6.148","lessThanOrEqual":"6.6.*","status":"unaffected","versionType":"semver"},{"version":"6.12.101","lessThanOrEqual":"6.12.*","status":"unaffected","versionType":"semver"},{"version":"6.18.42","lessThanOrEqual":"6.18.*","status":"unaffected","versionType":"semver"},{"version":"7.1.5","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":"4.3","versionEndExcluding":"5.10.266"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"5.15.217"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"6.1.184"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"6.6.148"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"6.12.101"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"6.18.42"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"7.1.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.3","versionEndExcluding":"7.2"}]}]}],"references":[{"url":"https://git.kernel.org/stable/c/7866116a040b3a23fb094e7d8f7ea3d61b3ac70b"},{"url":"https://git.kernel.org/stable/c/c5ef7228be04518d95591fc5369a9c554b19756d"},{"url":"https://git.kernel.org/stable/c/0aec339694a56e263d4b22475ff7211d40900830"},{"url":"https://git.kernel.org/stable/c/e64a48c50a1ff565a98c6a98d82b5b942868e76e"},{"url":"https://git.kernel.org/stable/c/c199ed687c00841daf60e9d131976958583a8c09"},{"url":"https://git.kernel.org/stable/c/09755dc62b026076b1d47f83489eb0547c8135e0"},{"url":"https://git.kernel.org/stable/c/b843a96252f672332837ea2ecb7c8db0acf68e20"},{"url":"https://git.kernel.org/stable/c/e5e24a365a5e024efef63cc49abb345fbd4852c5"}],"title":"netfilter: nf_conntrack_sip: validate skb_dst() before accessing it","x_generator":{"engine":"bippy-1.2.0"}}}}