{
  "cveId": "CVE-2022-49775",
  "url": "https://patchblox.com/security/cve/CVE-2022-49775",
  "summary": "CVE-2022-49775 is fixed in linux on 1 platform, first by DEBIAN-CVE-2022-49775, released May 1, 2025. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  tcp: cdg: allow tcp_cdg_release() to be called m...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  tcp: cdg: allow tcp_cdg_release() to be called multiple times  Apparently, mptcp is able to call tcp_disconnect() on an already disconnected flow. This is generally fine, unless current congestion control is CDG, because it might trigger a double-free [1]  Instead of fixing MPTCP, and future bugs, we can make tcp_disconnect() more resilient.  [1] BUG: KASAN: double-free in slab_free mm/slub.c:3539 [inline] BUG: KASAN: double-free in kfree\u002B0xe2/0x580 mm/slub.c:4567  CPU: 0 PID: 3645 Comm: kworker/0:7 Not tainted 6.0.0-syzkaller-02734-g0326074ff465 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/22/2022 Workqueue: events mptcp_worker Call Trace: \u003CTASK\u003E __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl\u002B0xcd/0x134 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:317 [inline] print_report.cold\u002B0x2ba/0x719 mm/kasan/report.c:433 kasan_report_invalid_free\u002B0x81/0x190 mm/kasan/report.c:462 ____kasan_slab_free\u002B0x18b/0x1c0 mm/kasan/common.c:356 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook\u002B0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree\u002B0xe2/0x580 mm/slub.c:4567 tcp_disconnect\u002B0x980/0x1e20 net/ipv4/tcp.c:3145 __mptcp_close_ssk\u002B0x5ca/0x7e0 net/mptcp/protocol.c:2327 mptcp_do_fastclose net/mptcp/protocol.c:2592 [inline] mptcp_worker\u002B0x78c/0xff0 net/mptcp/protocol.c:2627 process_one_work\u002B0x991/0x1610 kernel/workqueue.c:2289 worker_thread\u002B0x665/0x1080 kernel/workqueue.c:2436 kthread\u002B0x2e4/0x3a0 kernel/kthread.c:376 ret_from_fork\u002B0x1f/0x30 arch/x86/entry/entry_64.S:306 \u003C/TASK\u003E  Allocated by task 3671: kasan_save_stack\u002B0x1e/0x40 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:437 [inline] ____kasan_kmalloc mm/kasan/common.c:516 [inline] ____kasan_kmalloc mm/kasan/common.c:475 [inline] __kasan_kmalloc\u002B0xa9/0xd0 mm/kasan/common.c:525 kmalloc_array include/linux/slab.h:640 [inline] kcalloc include/linux/slab.h:671 [inline] tcp_cdg_init\u002B0x10d/0x170 net/ipv4/tcp_cdg.c:380 tcp_init_congestion_control\u002B0xab/0x550 net/ipv4/tcp_cong.c:193 tcp_reinit_congestion_control net/ipv4/tcp_cong.c:217 [inline] tcp_set_congestion_control\u002B0x96c/0xaa0 net/ipv4/tcp_cong.c:391 do_tcp_setsockopt\u002B0x505/0x2320 net/ipv4/tcp.c:3513 tcp_setsockopt\u002B0xd4/0x100 net/ipv4/tcp.c:3801 mptcp_setsockopt\u002B0x35f/0x2570 net/mptcp/sockopt.c:844 __sys_setsockopt\u002B0x2d6/0x690 net/socket.c:2252 __do_sys_setsockopt net/socket.c:2263 [inline] __se_sys_setsockopt net/socket.c:2260 [inline] __x64_sys_setsockopt\u002B0xba/0x150 net/socket.c:2260 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64\u002B0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe\u002B0x63/0xcd  Freed by task 16: kasan_save_stack\u002B0x1e/0x40 mm/kasan/common.c:38 kasan_set_track\u002B0x21/0x30 mm/kasan/common.c:45 kasan_set_free_info\u002B0x20/0x30 mm/kasan/generic.c:370 ____kasan_slab_free mm/kasan/common.c:367 [inline] ____kasan_slab_free\u002B0x166/0x1c0 mm/kasan/common.c:329 kasan_slab_free include/linux/kasan.h:200 [inline] slab_free_hook mm/slub.c:1759 [inline] slab_free_freelist_hook\u002B0x8b/0x1c0 mm/slub.c:1785 slab_free mm/slub.c:3539 [inline] kfree\u002B0xe2/0x580 mm/slub.c:4567 tcp_cleanup_congestion_control\u002B0x70/0x120 net/ipv4/tcp_cong.c:226 tcp_v4_destroy_sock\u002B0xdd/0x750 net/ipv4/tcp_ipv4.c:2254 tcp_v6_destroy_sock\u002B0x11/0x20 net/ipv6/tcp_ipv6.c:1969 inet_csk_destroy_sock\u002B0x196/0x440 net/ipv4/inet_connection_sock.c:1157 tcp_done\u002B0x23b/0x340 net/ipv4/tcp.c:4649 tcp_rcv_state_process\u002B0x40e7/0x4990 net/ipv4/tcp_input.c:6624 tcp_v6_do_rcv\u002B0x3fc/0x13c0 net/ipv6/tcp_ipv6.c:1525 tcp_v6_rcv\u002B0x2e8e/0x3830 net/ipv6/tcp_ipv6.c:1759 ip6_protocol_deliver_rcu\u002B0x2db/0x1950 net/ipv6/ip6_input.c:439 ip6_input_finish\u002B0x14c/0x2c0 net/ipv6/ip6_input.c:484 NF_HOOK include/linux/netfilter.h:302 [inline] NF_HOOK include/linux/netfilter.h:296 [inline] ip6_input\u002B0x9c/0xd ---truncated---",
  "published": "2025-05-01T15:16:00Z",
  "severity": "high",
  "cvss": 7.8,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
  "epss": 0.00212,
  "epssPercentile": 0.11541,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "6.0.10-1",
      "fix": "DEBIAN-CVE-2022-49775",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2022-49775",
      "released": "2025-05-01T15:16:00Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "6.0.10-1",
      "fix": "DEBIAN-CVE-2022-49775",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2022-49775",
      "released": "2025-05-01T15:16:00Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "6.0.10-1",
      "fix": "DEBIAN-CVE-2022-49775",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2022-49775",
      "released": "2025-05-01T15:16:00Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T06:59:42Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}