{ "dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": { "cveId": "CVE-2026-52981", "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "state": "PUBLISHED", "assignerShortName": "Linux", "dateReserved": "2026-06-09T07:44:35.376Z", "datePublished": "2026-06-24T16:28:57.074Z", "dateUpdated": "2026-08-05T12:32:19.237Z" }, "containers": { "cna": { "providerMetadata": { "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67", "shortName": "Linux", "dateUpdated": "2026-08-05T12:32:19.237Z" }, "descriptions": [ { "lang": "en", "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nneigh: let neigh_xmit take skb ownership\n\nneigh_xmit always releases the skb, except when no neighbour table is\nfound. But even the first added user of neigh_xmit (mpls) relied on\nneigh_xmit to release the skb (or queue it for tx).\n\nsashiko reported:\n If neigh_xmit() is called with an uninitialized neighbor table (for\n example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT\n and bypasses its internal out_kfree_skb error path. Because the return\n value of neigh_xmit() is ignored here, does this leak the SKB?\n\nAssume full ownership and remove the last code path that doesn't\nxmit or free skb." } ], "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 - An unauthenticated packet sender can trigger the vulnerable `neigh_xmit()` path through configured network forwarding paths such as nftables netdev forwarding or MPLS forwarding. In the highest reasonable deployment, this is an exposed router/firewall datapath reachable by network traffic.\nAC:L - The bug is deterministic once the forwarding path uses a real neighbor table whose pointer is NULL, such as `NEIGH_ND_TABLE` when IPv6 neighbor discovery is unavailable. No race or heap shaping is required; repeated matching packets repeatedly leak skbs.\nPR:N - The attacker does not need privileges to send packets into an already configured vulnerable forwarding datapath. Although installing such rules/routes requires administrative network privileges, the packet-triggering attack itself is unauthenticated.\nUI:N - No victim user action is required after the affected forwarding configuration exists. The attacker only sends traffic that reaches the vulnerable path.\nS:U - The impact remains within the kernel/networking security authority of the affected system. There is no VM escape, sandbox boundary crossing, or separate security scope involved.\nC:N - The flaw is an skb memory leak caused by failing to free the packet buffer on the missing-table error path. It does not expose leaked memory contents to the attacker.\nI:N - The bug does not provide a memory corruption or data modification primitive. It only loses ownership of allocated skbs.\nA:H - An attacker can repeatedly trigger the leak with packets, consuming kernel memory and plausibly causing OOM, hangs, packet processing failure, or system-wide denial of service. Kernel memory exhaustion is a high availability impact." } ] } ], "affected": [ { "product": "Linux", "vendor": "Linux", "defaultStatus": "unaffected", "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git", "programFiles": [ "net/core/neighbour.c" ], "versions": [ { "version": "4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62", "lessThan": "8a89054a1ec0767aec25ed2bbac933da6ba3cf5a", "status": "affected", "versionType": "git" }, { "version": "4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62", "lessThan": "9247d59ca15bf60a57dca08103f055d8a4340877", "status": "affected", "versionType": "git" }, { "version": "4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62", "lessThan": "0084712e0bee204b284510cdb63182fd5a30c2b7", "status": "affected", "versionType": "git" }, { "version": "4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62", "lessThan": "63063ba60d2dc334e34f1e3f9271d7f3f6f30307", "status": "affected", "versionType": "git" }, { "version": "4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62", "lessThan": "445e45a2c3a078316a62d2d331a570cf34ef5079", "status": "affected", "versionType": "git" }, { "version": "4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62", "lessThan": "4438113be604ee67a7bf4f81da6e1cca41332ce4", "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/core/neighbour.c" ], "versions": [ { "version": "4.1", "status": "affected" }, { "version": "0", "lessThan": "4.1", "status": "unaffected", "versionType": "semver" }, { "version": "6.1.175", "lessThanOrEqual": "6.1.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.6.141", "lessThanOrEqual": "6.6.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.12.91", "lessThanOrEqual": "6.12.*", "status": "unaffected", "versionType": "semver" }, { "version": "6.18.33", "lessThanOrEqual": "6.18.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.0.10", "lessThanOrEqual": "7.0.*", "status": "unaffected", "versionType": "semver" }, { "version": "7.1", "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": "4.1", "versionEndExcluding": "6.1.175" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.6.141" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.12.91" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "6.18.33" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "7.0.10" }, { "vulnerable": true, "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*", "versionStartIncluding": "4.1", "versionEndExcluding": "7.1" } ] } ] } ], "references": [ { "url": "https://git.kernel.org/stable/c/8a89054a1ec0767aec25ed2bbac933da6ba3cf5a" }, { "url": "https://git.kernel.org/stable/c/9247d59ca15bf60a57dca08103f055d8a4340877" }, { "url": "https://git.kernel.org/stable/c/0084712e0bee204b284510cdb63182fd5a30c2b7" }, { "url": "https://git.kernel.org/stable/c/63063ba60d2dc334e34f1e3f9271d7f3f6f30307" }, { "url": "https://git.kernel.org/stable/c/445e45a2c3a078316a62d2d331a570cf34ef5079" }, { "url": "https://git.kernel.org/stable/c/4438113be604ee67a7bf4f81da6e1cca41332ce4" } ], "title": "neigh: let neigh_xmit take skb ownership", "x_generator": { "engine": "bippy-1.2.0" } } } }