{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.1.187-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.105-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.1.9-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux-6.12"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "6.12.107-1~deb12u1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  bpf, sockmap: Fix sk_redir use-after-free in send verdict  sk_psock_msg_verdict() takes a socket reference for psock-\u003esk_redir. tcp_bpf_send_verdict() copies that pointer while holding the source socket lock, but does not take a reference for the local copy before dropping the lock around tcp_bpf_sendmsg_redir().  When apply_bytes keeps the cached verdict active, another sendmsg() on the same source socket can consume the remaining bytes and release the cached reference while the first thread still holds only the raw local pointer:    CPU 0                                  CPU 1   sk_redir = psock-\u003esk_redir   apply_bytes remains nonzero   release_sock(sk)                                          lock_sock(sk)                                          apply_bytes reaches zero                                          psock-\u003esk_redir = NULL                                          release_sock(sk)                                          tcp_bpf_sendmsg_redir(sk_redir)                                          sock_put(sk_redir)   tcp_bpf_sendmsg_redir(sk_redir)  The final sock_put() can free sk_redir before CPU 0 dereferences it.  KASAN reported:    BUG: KASAN: slab-use-after-free in tcp_bpf_sendmsg_redir+0xf39/0x1020   Read of size 8 at addr ffff888108537090 by task poc/87   Call Trace:    tcp_bpf_sendmsg_redir+0xf39/0x1020    tcp_bpf_sendmsg+0x977/0x1a50    __sys_sendto+0x32c/0x3a0    __x64_sys_sendto+0xdb/0x1b0   Allocated by task 85:    sk_prot_alloc+0x56/0x210    sk_clone+0x6f/0x14b0    inet_csk_clone_lock+0x24/0x740    tcp_create_openreq_child+0x25/0x2710    tcp_v4_syn_recv_sock+0x10a/0xe00   Freed by task 0:    __kasan_slab_free+0x43/0x70    slab_free_after_rcu_debug+0xa6/0x1e0    rcu_core+0x50a/0x1850   Last potentially related work creation:    __sk_destruct+0x3da/0x540    sk_psock_destroy+0x81e/0xab0    process_one_work+0x63a/0x1070  Take a temporary socket reference while the source socket lock still protects psock-\u003esk_redir, and drop it after tcp_bpf_sendmsg_redir() returns.  This keeps each unlocked use independent of cached-verdict ownership.",
  "id": "DEBIAN-CVE-2026-74589",
  "modified": "2026-09-19T21:47:23.114508565Z",
  "published": "2026-08-22T16:16:31.097Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-74589"
    }
  ],
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
      "type": "CVSS_V3"
    }
  ],
  "upstream": [
    "CVE-2026-74589"
  ]
}