{"id":"CVE-2026-31679","state":"PUBLISHED","title":"openvswitch: validate MPLS set/set_masked payload length","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: validate MPLS set/set_masked payload length\n\nvalidate_set() accepted OVS_KEY_ATTR_MPLS as variable-sized payload for\nSET/SET_MASKED actions. In action handling, OVS expects fixed-size\nMPLS key data (struct ovs_key_mpls).\n\nUse the already normalized key_len (masked case included) and reject\nnon-matching MPLS action key sizes.\n\nReject invalid MPLS action payload lengths early.","publishedAt":"2026-04-25T08:46:55.584Z","updatedAt":"2026-10-19T18:56:04.364Z","severity":{"score":7.1,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"68f32ef0683c8d1c05cd2e4f16818fa63ff59c6f","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"4cae986225f8b8679ad86b924918e7d75a96aa61","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"8ed7b9930cbc3bc71f868fa79a68700ac88d586a","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"c1f97152df8dfb17e855ddf0fc409b7bd13e9700","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"98de18d327ef8cbbb704980e359e4872d8c28997","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"bd50c7484c3bb34097571c1334174fb8b7408036","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"2ca33b88a79ca42f017ae0f7011280325655438e","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"546b68ac893595877ffbd7751e5c55fd1c43ede6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/openvswitch/flow_netlink.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.168","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.131","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.80","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.21","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.11","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/openvswitch/flow_netlink.c"]}],"references":["https://git.kernel.org/stable/c/68f32ef0683c8d1c05cd2e4f16818fa63ff59c6f","https://git.kernel.org/stable/c/4cae986225f8b8679ad86b924918e7d75a96aa61","https://git.kernel.org/stable/c/8ed7b9930cbc3bc71f868fa79a68700ac88d586a","https://git.kernel.org/stable/c/c1f97152df8dfb17e855ddf0fc409b7bd13e9700","https://git.kernel.org/stable/c/98de18d327ef8cbbb704980e359e4872d8c28997","https://git.kernel.org/stable/c/bd50c7484c3bb34097571c1334174fb8b7408036","https://git.kernel.org/stable/c/2ca33b88a79ca42f017ae0f7011280325655438e","https://git.kernel.org/stable/c/546b68ac893595877ffbd7751e5c55fd1c43ede6"],"weaknesses":["CWE-20"],"ingestedAt":"2026-10-29T20:11:40.391Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/31xxx/CVE-2026-31679.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-31679","state":"PUBLISHED","datePublished":"2026-04-25T08:46:55.584Z","dateUpdated":"2026-10-19T18:56:04.364Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-03-09T15:48:24.130Z"},"containers":{"cna":{"title":"openvswitch: validate MPLS set/set_masked payload length","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nopenvswitch: validate MPLS set/set_masked payload length\n\nvalidate_set() accepted OVS_KEY_ATTR_MPLS as variable-sized payload for\nSET/SET_MASKED actions. In action handling, OVS expects fixed-size\nMPLS key data (struct ovs_key_mpls).\n\nUse the already normalized key_len (masked case included) and reject\nnon-matching MPLS action key sizes.\n\nReject invalid MPLS action payload lengths early."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"68f32ef0683c8d1c05cd2e4f16818fa63ff59c6f","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"4cae986225f8b8679ad86b924918e7d75a96aa61","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"8ed7b9930cbc3bc71f868fa79a68700ac88d586a","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"c1f97152df8dfb17e855ddf0fc409b7bd13e9700","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"98de18d327ef8cbbb704980e359e4872d8c28997","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"bd50c7484c3bb34097571c1334174fb8b7408036","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"2ca33b88a79ca42f017ae0f7011280325655438e","versionType":"git"},{"version":"fbdcdd78da7c95f1b970d371e1b23cbd3aa990f3","status":"affected","lessThan":"546b68ac893595877ffbd7751e5c55fd1c43ede6","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/openvswitch/flow_netlink.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"5.5","status":"affected"},{"version":"0","status":"unaffected","lessThan":"5.5","versionType":"semver"},{"version":"5.10.253","status":"unaffected","lessThanOrEqual":"5.10.*","versionType":"semver"},{"version":"5.15.203","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.168","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.131","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.80","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.21","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"6.19.11","status":"unaffected","lessThanOrEqual":"6.19.*","versionType":"semver"},{"version":"7.0","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["net/openvswitch/flow_netlink.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/68f32ef0683c8d1c05cd2e4f16818fa63ff59c6f"},{"url":"https://git.kernel.org/stable/c/4cae986225f8b8679ad86b924918e7d75a96aa61"},{"url":"https://git.kernel.org/stable/c/8ed7b9930cbc3bc71f868fa79a68700ac88d586a"},{"url":"https://git.kernel.org/stable/c/c1f97152df8dfb17e855ddf0fc409b7bd13e9700"},{"url":"https://git.kernel.org/stable/c/98de18d327ef8cbbb704980e359e4872d8c28997"},{"url":"https://git.kernel.org/stable/c/bd50c7484c3bb34097571c1334174fb8b7408036"},{"url":"https://git.kernel.org/stable/c/2ca33b88a79ca42f017ae0f7011280325655438e"},{"url":"https://git.kernel.org/stable/c/546b68ac893595877ffbd7751e5c55fd1c43ede6"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H","baseScore":7.1,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:L - The vulnerable path is reached through Open vSwitch generic netlink commands that install or execute datapath actions, not by unauthenticated remote packets alone.\nAC:L - An attacker can craft the malformed MPLS SET/SET_MASKED netlink attributes and an MPLS packet directly; there is no race or victim-controlled timing requirement.\nPR:L - The relevant OVS commands require CAP_NET_ADMIN, but the families are netns-aware and use GENL_UNS_ADMIN_PERM, making them reachable with CAP_NET_ADMIN in a user-created network namespace.\nUI:N - No victim interaction is required once the attacker can send the crafted netlink request or trigger the installed action.\nS:U - The impact remains within the kernel/host networking security authority and does not cross a VM, IOMMU, or similar scope boundary.\nC:H - The invalid MPLS payload length can make action execution read beyond the validated netlink action data from kernel heap storage. Although each read is small, repeated attacker-controlled triggering and heap layout influence make high confidentiality impact the safer defensible choice.\nI:N - The bug causes out-of-bounds reads and attacker-influenced packet MPLS rewriting, but it does not provide a kernel memory write primitive or control-flow modification.\nA:H - The out-of-bounds kernel heap read can trigger a kernel fault or sanitizer-detected panic, and the crafted action can be exercised repeatedly without user interaction."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-08-05T12:24:25.701Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.10.253"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"5.15.203"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.1.168"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.6.131"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.12.80"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.18.21"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"6.19.11"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"5.5","versionEndExcluding":"7.0"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-31679","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-10-16T15:12:20.188389Z"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-20","lang":"en","type":"CWE","description":"CWE-20 Improper Input Validation"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-19T18:56:04.364Z"}}]}}}