CVE-2026-52981 (GCVE-0-2026-52981)

Vulnerability from cvelistv5 – Published: 2026-06-24 16:28 – Updated: 2026-08-05 12:32
VLAI
Title
neigh: let neigh_xmit take skb ownership
Summary
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
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 8a89054a1ec0767aec25ed2bbac933da6ba3cf5a (git)
Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 9247d59ca15bf60a57dca08103f055d8a4340877 (git)
Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 0084712e0bee204b284510cdb63182fd5a30c2b7 (git)
Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 63063ba60d2dc334e34f1e3f9271d7f3f6f30307 (git)
Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 445e45a2c3a078316a62d2d331a570cf34ef5079 (git)
Affected: 4fd3d7d9e868ffbdb0e7a67c5c8e9dfdcd846a62 , < 4438113be604ee67a7bf4f81da6e1cca41332ce4 (git)
Create a notification for this product.
Linux Linux Affected: 4.1
Unaffected: 0 , < 4.1 (semver)
Unaffected: 6.1.175 , ≤ 6.1.* (semver)
Unaffected: 6.6.141 , ≤ 6.6.* (semver)
Unaffected: 6.12.91 , ≤ 6.12.* (semver)
Unaffected: 6.18.33 , ≤ 6.18.* (semver)
Unaffected: 7.0.10 , ≤ 7.0.* (semver)
Unaffected: 7.1 , ≤ * (original_commit_for_fix)
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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\u0027t\\nxmit or free 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      "cve": "CVE-2026-52981",
      "id": "CVE-2026-52981",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: neigh: let neigh_xmit take skb ownership",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-52981.json",
      "version": "3"
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    "suse_vex": {
      "aggregate_severity": "low",
      "current_release_date": "2026-07-21T23:52:04Z",
      "cve": "CVE-2026-52981",
      "id": "CVE-2026-52981",
      "initial_release_date": "2026-06-27T01:55:03Z",
      "product_status:known_affected": "15",
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      "product_status:recommended": "98",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2026-52981",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2026-52981.json",
      "version": "3"
    }
  }
}



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