{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-80681", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-08-26T14:34:25.783Z", "datePublished": "2026-08-28T06:52:48.896Z", "dateUpdated": "2026-10-16T19:26:32.921Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-29T06:22:07.840Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nvxlan: re-fetch eth header after route_shortcircuit()\n\nBefore route_shortcircuit(), the eth header pointer is cached from eth_hdr(skb).\n\nInside route_shortcircuit(), pskb_may_pull() can be called, which may\nreallocate skb->head.\n\nIn this case, returning to vxlan_xmit() leaves the cached eth pointer pointing to\nfreed memory, leading to a use-after-free when dereferencing eth->h_dest.\n\nFix this by updating eth = eth_hdr(skb) after calling route_shortcircuit()." } ], "metrics": [ { "cvssV3_1": { "version": "3.1", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H", "baseScore": 9.8, "baseSeverity": "CRITICAL" }, "scenarios": [ { "lang": "en", "value": "AV:N - The bug is in vxlan_xmit(), reached when the kernel transmits packets out a VXLAN netdev via routing, bridging, or overlay forwarding; remote peers can inject IPv4/IPv6 Ethernet frames that traverse this TX path on cloud, Kubernetes, and data-center VXLAN deployments.\nAC:L - An attacker controlling overlay or forwarded traffic can reliably meet RSC prerequisites (router FDB entry, IPv4/IPv6 ethertype, neighbour MAC mismatch, cloned/nonlinear skb) so route_shortcircuit() calls pskb_may_pull/skb_cow_head and reallocates skb->head, invalidating the cached eth pointer.\nPR:N - Exploitation requires only sending network traffic processed by an existing VXLAN interface with RSC enabled, not host administrator credentials; remote overlay peers and unauthenticated senders whose packets are forwarded through VXLAN need no elevated privileges on the target.\nUI:N - The use-after-free is triggered automatically during kernel packet transmit processing in vxlan_xmit() with no action required from a local user or administrator beyond normal network operation on a VXLAN-enabled host.\nS:U - The stale eth_hdr pointer causes heap use-after-free within the kernel's own memory domain during VXLAN transmit processing; impact is standard in-kernel memory corruption and does not inherently cross VM, container, or IOMMU security boundaries.\nC:H - After route_shortcircuit() reallocates skb->head, vxlan_xmit() dereferences the stale eth pointer for eth->h_dest, constituting a heap use-after-free read that can disclose adjacent freed slab contents and support further kernel memory disclosure primitives.\nI:H - Use-after-free of the Ethernet header buffer in skb head memory enables attacker-controlled reuse of freed kmalloc slabs, a well-established path to heap grooming and arbitrary kernel memory corruption or control-flow hijacking beyond the immediate MAC header read.\nA:H - Dereferencing a freed skb head pointer in vxlan_xmit() can cause an immediate kernel oops or panic from invalid memory access, and UAF heap corruption routinely destabilizes or crashes the system even when full exploitation is not pursued." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/vxlan/vxlan_core.c" ], "versions": [ { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "6375093eb45cd7d89f1945f939eeae3b29d79f56", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "1b7f7b653e3557690047c62f03b80a24ea5a58a5", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "bf045341dfb3e767f0ff94cf240ce3c371973bd4", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "2355c8c26d2aa1b4385b369e67202e47d460d555", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "1511631b7cfc4152b10a0a9d04c7a0bf2ddf4585", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "1235e017aa11cf01e91b613c4c5ed6aa28934fff", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "c9dceac9e1c7c772c43c732fc0d325e72835801a", "status": "affected", "versionType": "git" }, { "version": "ae8840825605f36f98f247323edc150e761cb64e", "lessThan": "1395a676ec15a0a02a2a6d86602324f2d5fd41d5", "status": "affected", "versionType": "git" } ] }, { "product": "Linux", "vendor": "Linux", "defaultStatus": "affected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "drivers/net/vxlan/vxlan_core.c" ], "versions": [ { "version": "3.10", "status": "affected" }, { "version": "0", "lessThan": "3.10", "status": "unaffected", "versionType": "semver" }, { "version": "5.10.265", "lessThanOrEqual": "5.10.*", "status": "unaffected", "versionType": "semver" }, { "version": "5.15.216", "lessThanOrEqual": "5.15.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.183", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.151", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.103", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.44", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1.8", "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": "3.10", "versionEndExcluding": "5.10.265" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "5.15.216" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.1.183" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.6.151" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.12.103" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "6.18.44" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.1.8" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "3.10", "versionEndExcluding": "7.2" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/6375093eb45cd7d89f1945f939eeae3b29d79f56" }, { "url": "https://git.kernel.org/stable/c/1b7f7b653e3557690047c62f03b80a24ea5a58a5" }, { "url": "https://git.kernel.org/stable/c/bf045341dfb3e767f0ff94cf240ce3c371973bd4" }, { "url": "https://git.kernel.org/stable/c/2355c8c26d2aa1b4385b369e67202e47d460d555" }, { "url": "https://git.kernel.org/stable/c/1511631b7cfc4152b10a0a9d04c7a0bf2ddf4585" }, { "url": "https://git.kernel.org/stable/c/1235e017aa11cf01e91b613c4c5ed6aa28934fff" }, { "url": "https://git.kernel.org/stable/c/c9dceac9e1c7c772c43c732fc0d325e72835801a" }, { "url": "https://git.kernel.org/stable/c/1395a676ec15a0a02a2a6d86602324f2d5fd41d5" } ], "title": "vxlan: re-fetch eth header after route_shortcircuit()", "x_generator": { "engine": "bippy-1.2.0" } }, "adp": [ { "metrics": [ { "other": { "type": "ssvc", "content": { "id": "CVE-2026-80681", "role": "CISA Coordinator", "options": [ { "Exploitation": "none" }, { "Automatable": "yes" }, { "Technical Impact": "total" } ], "version": "2.0.3", "timestamp": "2026-10-16T19:19:50.454403Z" } } } ], "title": "CISA ADP Vulnrichment", "providerMetadata": { "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-10-16T19:26:32.921Z" } } ] } }