{
  "affected": [
    {
      "ranges": [
        {
          "events": [
            {
              "introduced": "5800b1cf3fd8ccab752a101865be1e76dac33142"
            },
            {
              "fixed": "9ada3931beb37068fcb725b34b0398457009f343"
            },
            {
              "fixed": "5f470cc883416fea6d3bce18ef96bf91dd49ffc3"
            },
            {
              "fixed": "5801cff7d5d7b4e9d877dfb627b23eb63167f02c"
            }
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "type": "GIT"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "Linux",
        "name": "Kernel"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "6.16.0"
            },
            {
              "fixed": "6.18.40"
            }
          ],
          "type": "ECOSYSTEM"
        },
        {
          "events": [
            {
              "introduced": "6.19.0"
            },
            {
              "fixed": "7.1.5"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "Linux",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74434.json"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: Don't move a peeked OOB message onto the pending queue\n\nrxrpc_recvmsg_oob() takes a received oob message off recvmsg_oobq and,\nif a response is needed, moves it onto the pending_oobq tree. However,\nonly the unlink from recvmsg_oobq is guarded by MSG_PEEK; the move onto\npending_oobq always runs.\n\nAs a result, reading a challenge with MSG_PEEK leaves the skb on\nrecvmsg_oobq while also adding it to pending_oobq. Since struct\nsk_buff's rbnode shares storage with its next and prev pointers,\nrb_insert_color() overwrites the list linkage, and the skb, which holds\na single reference, becomes reachable from both queues at once.\n\nWhen the socket is closed both queues are drained in turn. While\ndraining recvmsg_oobq, __skb_unlink() follows the next and prev\npointers that rbnode has overwritten and writes to a bad address. Also,\nas the skb holds a single reference but is freed from each queue, both\nthe skb and the connection reference it holds are released twice. This\nleads to memory corruption and to a use-after-free caused by the\nconnection refcount underflow.\n\nMSG_PEEK does not consume the message from the queue, so only unlink it\nfrom recvmsg_oobq and then move it onto pending_oobq or free it when\nthe message is actually consumed.",
  "id": "CVE-2026-74434",
  "modified": "2026-08-18T03:31:01.138405243Z",
  "published": "2026-08-15T05:59:33.438Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5801cff7d5d7b4e9d877dfb627b23eb63167f02c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5f470cc883416fea6d3bce18ef96bf91dd49ffc3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/9ada3931beb37068fcb725b34b0398457009f343"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/74xxx/CVE-2026-74434.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-74434"
    },
    {
      "type": "PACKAGE",
      "url": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "summary": "rxrpc: Don't move a peeked OOB message onto the pending queue"
}