{
  "cveId": "CVE-2026-80849",
  "url": "https://patchblox.com/security/cve/CVE-2026-80849",
  "summary": "CVE-2026-80849 is fixed in 2 products on 1 platform, first by DEBIAN-CVE-2026-80849, released September 11, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  net/tcp-ao: fix use-after-free of current_key on...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  net/tcp-ao: fix use-after-free of current_key on reconnect to another peer  tcp_inbound_ao_hash() is called before bh_lock_sock_nested() is taken, with only rcu_read_lock() held. On the fast path for established sockets, if the rnext_keyid sent by the peer differs from current_key-\u003Esndid, the key the peer asked for is looked up and stored in current_key. The lookup is inside the RCU read side, but current_key outlives it.  When the socket is disconnected and connect() is called again for another peer, tcp_ao_connect_init() unlinks every key that does not match the new peer and frees it with call_rcu(). If current_key points at such a key, it is cleared to NULL.  The fast path reads sk_state only once on entry, so a softirq that got into it while the socket was still established can update current_key after that loop has already run. The update is inside the RCU read side, so it comes before the call_rcu() callback, and once the callback frees the key, current_key is left pointing at freed memory.  The next transmission picks that pointer up in tcp_get_current_key(). tcp_ao_transmit_skb() then reads the traffic key from the freed object, which is the use-after-free.  Wait for one grace period before unlinking, and only if a key is going to be removed. By the time tcp_connect() runs the socket is already in TCP_SYN_SENT, and TCP_AO_ESTABLISHED does not contain TCPF_SYN_SENT, so a softirq entering after the wait cannot reach the fast path, and the ones already in it have finished. The existing NULL handling in the loop is then enough.",
  "published": "2026-09-04T16:18:13Z",
  "severity": "",
  "epss": 0.00168,
  "epssPercentile": 0.06131,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.12.111-1",
      "fix": "DEBIAN-CVE-2026-80849",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80849",
      "released": "2026-09-11T12:23:55Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.1.13-1",
      "fix": "DEBIAN-CVE-2026-80849",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80849",
      "released": "2026-09-11T12:23:55Z"
    },
    {
      "platform": "linux",
      "product": "linux-6.12",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.12.111-1~deb12u1",
      "fix": "DEBIAN-CVE-2026-80849",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-80849",
      "released": "2026-09-11T12:23:55Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}