{"id":"CVE-2026-97612","title":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mpls: clear inner_protocol when the last label is popped\n\nskb_mpls_push() records the pre-encapsulation network header once, gated\non !skb->inner_protocol","summary":"In the Linux kernel, the following vulnerability has been resolved:\n\nnet: mpls: clear inner_protocol when the last label is popped\n\nskb_mpls_push() records the pre-encapsulation network header once, gated\non !skb->inner_protocol. skb_mpl…","severity":"high","cvss":7.8,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-805","CWE-787"],"vendor":"Linux","product":"Linux","affected":["Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < 55ed97db27bffe29c21fdefd5d25601322c36ff8","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < 833ec2788322306407503b4cfc7745cd1f9d785f","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < 38db09804b2616aa1e2fcdf97f0c3ae8b9dbdd34","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < 0b3425fd0ecd515997956f7bb8a8a576b444ed64","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < 011e17b5cae19b9f6a150923275e41c278de64f0","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < da8c3a7f5d3137fec4ff60a6248f5f6d66b6a63e","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < b39120523475d6b436be7f6cb27d48064148a327","Linux >= 48d2ab609b6bbecb7698487c8579bc40de9d6dfa < 78a86d75a70e1e227711c72865c59b1422d0a5ae","Linux 4.9"],"published":"2026-09-25","updated":"2026-10-03","sourceUpdated":"2026-10-03T11:18:07.643","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-97612","references":[{"url":"https://git.kernel.org/stable/c/011e17b5cae19b9f6a150923275e41c278de64f0","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/0b3425fd0ecd515997956f7bb8a8a576b444ed64","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/38db09804b2616aa1e2fcdf97f0c3ae8b9dbdd34","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/55ed97db27bffe29c21fdefd5d25601322c36ff8","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/78a86d75a70e1e227711c72865c59b1422d0a5ae","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/833ec2788322306407503b4cfc7745cd1f9d785f","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/b39120523475d6b436be7f6cb27d48064148a327","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://git.kernel.org/stable/c/da8c3a7f5d3137fec4ff60a6248f5f6d66b6a63e","label":"416baaa9-dc9f-4396-8d5f-8c081fb06d67"},{"url":"https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97612.json"},{"url":"https://access.redhat.com/security/cve/CVE-2026-97612"},{"url":"https://bugzilla.redhat.com/show_bug.cgi?id=2541154"},{"url":"https://www.cve.org/CVERecord?id=CVE-2026-97612"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-97612"},{"url":"https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2026/CVE-2026-97612.mbox"},{"url":"https://kernelcve.org/list/?q=CVE-2026-97612"}],"tags":["nvd","cve.org","csaf","vex","red-hat","score-dispute"],"epss":0.00169,"epssPercentile":0.0619,"scores":{"nvd":7.8,"vendor":5.5,"cna":7.8},"ingestedAt":"2026-09-25T11:06:38.899Z","slug":"CVE-2026-97612","body":"## Overview\n\nIn the Linux kernel, the following vulnerability has been resolved:\n\nnet: mpls: clear inner_protocol when the last label is popped\n\nskb_mpls_push() records the pre-encapsulation network header once, gated\non !skb->inner_protocol. skb_mpls_pop() never clears that record, so it\noutlives the encapsulation it describes.\n\nOpen vSwitch can then re-push MPLS onto a packet whose\ninner_network_header still points at the older, deeper offset: push a\nlabel, pop every label, recirculate (ovs_flow_key_update() re-derives\nkey->eth.type and resets network_header, but leaves inner_*), then push\nagain. ovs_fragment() trusts the record:\n\n\tskb->network_header = skb->inner_network_header;\n\nso skb_network_offset() goes negative. The bound check is signed:\n\n\tif (skb_network_offset(skb) > MAX_L2_LEN)\n\na negative offset passes it, and prepare_frag() widens the value:\n\n\tunsigned int hlen = skb_network_offset(skb);\n\tmemcpy(&data->l2_data, skb->data, hlen);\n\nwhich is a ~4GiB memcpy out of a 30-byte per-CPU buffer.\n\nReproduced on v7.3-rc1. RDX is the truncated length, (unsigned int)(-8):\n\n  BUG: unable to handle page fault for address: ffffe8ffffc16000\n  #PF: supervisor write access in kernel mode\n  Oops: 0002 [#1] SMP KASAN NOPTI\n  RIP: 0010:memcpy+0x8/0x20\n  RDX: 00000000fffffff8 RSI: ffff888105d732db RDI: ffffe8ffffc16000\n   prepare_frag+0x3df/0x4e0\n   ovs_fragment+0x589/0x7e0\n   do_output+0x4ce/0x5e0\n   do_execute_actions+0x55d2/0x7b30\n   ovs_execute_actions+0xea/0x450\n\nSame root-cause shape as commit 975b5b067f52 (\"ipv6: sr: restore network\nheader before routing and forwarding\"): a stale network header offset\nreaching a consumer that widens it. Here it originates in the MPLS\npush/pop path.\n\nClear inner_protocol once the packet is no longer MPLS, so a later push\nre-records the current header. net/sched/act_mpls.c is the only other\nskb_mpls_pop() caller and gets the same fix; sch_frag.c saves and\nrestores inner_protocol around fragmentation in the same way OVS does.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Vendor advisories\n\n- **Red Hat VEX** · Moderate · affected: Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, Red Hat Enterprise Linux 9, Red Hat OpenShift Container Platform 4 · no fix planned: Red Hat Enterprise Linux 6, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 7, Red Hat Enterprise Linux 8, … · updated 2026-10-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-97612.json)","depth":"twilight","depthScore":43,"depthScoreParts":{"impact":42.9,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[{"seq":210962,"id":"CVE-2026-97612","ts":1790349119306,"field":"cvss","old":null,"new":"7.8"},{"seq":210961,"id":"CVE-2026-97612","ts":1790349119306,"field":"severity","old":"none","new":"high"}]}