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CVE-2026-52981

Full vulnerability record from the local CVENow database.

Description

In the Linux kernel, the following vulnerability has been resolved: neigh: let neigh_xmit take skb ownership neigh_xmit always releases the skb, except when no neighbour table is found. But even the first added user of neigh_xmit (mpls) relied on neigh_xmit to release the skb (or queue it for tx). sashiko reported: If neigh_xmit() is called with an uninitialized neighbor table (for example, NEIGH_ND_TABLE when IPv6 is disabled), it returns -EAFNOSUPPORT and bypasses its internal out_kfree_skb error path. Because the return value of neigh_xmit() is ignored here, does this leak the SKB? Assume full ownership and remove the last code path that doesn't xmit or free skb.

Severity
HIGH
CVSS score
7.5 (v3.1)
Vulnerability status
Modified
Source identifier
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Published
2026-06-24 17:17:08.723000
Last modified
2026-10-19 20:18:52.770000
View original CVE JSON
{
  "id": "CVE-2026-52981",
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "published": "2026-06-24T17:17:08.723",
  "lastModified": "2026-10-19T20:18:52.770",
  "vulnStatus": "Modified",
  "cveTags": [],
  "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."
    }
  ],
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      "affectedData": [
        {
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          "product": "Linux",
          "defaultStatus": "unaffected",
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            "net/core/neighbour.c"
          ],
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            },
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              "version": "6.18.33",
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              "versionType": "semver",
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            },
            {
              "version": "7.0.10",
              "lessThanOrEqual": "7.0.*",
              "versionType": "semver",
              "status": "unaffected"
            },
            {
              "version": "7.1",
              "lessThanOrEqual": "*",
              "versionType": "original_commit_for_fix",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
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          "role": "CISA Coordinator",
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  "weaknesses": [
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      "source": "[email protected]",
      "type": "Primary",
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}