{
  "cveId": "CVE-2021-47588",
  "url": "https://patchblox.com/security/cve/CVE-2021-47588",
  "summary": "CVE-2021-47588 is fixed in linux on 1 platform, first by DEBIAN-CVE-2021-47588, released June 19, 2024. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  sit: do not call ipip6_dev_free() from sit_init_...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  sit: do not call ipip6_dev_free() from sit_init_net()  ipip6_dev_free is sit dev-\u003Epriv_destructor, already called by register_netdevice() if something goes wrong.  Alternative would be to make ipip6_dev_free() robust against multiple invocations, but other drivers do not implement this strategy.  syzbot reported:  dst_release underflow WARNING: CPU: 0 PID: 5059 at net/core/dst.c:173 dst_release\u002B0xd8/0xe0 net/core/dst.c:173 Modules linked in: CPU: 1 PID: 5059 Comm: syz-executor.4 Not tainted 5.16.0-rc5-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:dst_release\u002B0xd8/0xe0 net/core/dst.c:173 Code: 4c 89 f2 89 d9 31 c0 5b 41 5e 5d e9 da d5 44 f9 e8 1d 90 5f f9 c6 05 87 48 c6 05 01 48 c7 c7 80 44 99 8b 31 c0 e8 e8 67 29 f9 \u003C0f\u003E 0b eb 85 0f 1f 40 00 53 48 89 fb e8 f7 8f 5f f9 48 83 c3 a8 48 RSP: 0018:ffffc9000aa5faa0 EFLAGS: 00010246 RAX: d6894a925dd15a00 RBX: 00000000ffffffff RCX: 0000000000040000 RDX: ffffc90005e19000 RSI: 000000000003ffff RDI: 0000000000040000 RBP: 0000000000000000 R08: ffffffff816a1f42 R09: ffffed1017344f2c R10: ffffed1017344f2c R11: 0000000000000000 R12: 0000607f462b1358 R13: 1ffffffff1bfd305 R14: ffffe8ffffcb1358 R15: dffffc0000000000 FS:  00007f66c71a2700(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f88aaed5058 CR3: 0000000023e0f000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace:  \u003CTASK\u003E  dst_cache_destroy\u002B0x107/0x1e0 net/core/dst_cache.c:160  ipip6_dev_free net/ipv6/sit.c:1414 [inline]  sit_init_net\u002B0x229/0x550 net/ipv6/sit.c:1936  ops_init\u002B0x313/0x430 net/core/net_namespace.c:140  setup_net\u002B0x35b/0x9d0 net/core/net_namespace.c:326  copy_net_ns\u002B0x359/0x5c0 net/core/net_namespace.c:470  create_new_namespaces\u002B0x4ce/0xa00 kernel/nsproxy.c:110  unshare_nsproxy_namespaces\u002B0x11e/0x180 kernel/nsproxy.c:226  ksys_unshare\u002B0x57d/0xb50 kernel/fork.c:3075  __do_sys_unshare kernel/fork.c:3146 [inline]  __se_sys_unshare kernel/fork.c:3144 [inline]  __x64_sys_unshare\u002B0x34/0x40 kernel/fork.c:3144  do_syscall_x64 arch/x86/entry/common.c:50 [inline]  do_syscall_64\u002B0x44/0xd0 arch/x86/entry/common.c:80  entry_SYSCALL_64_after_hwframe\u002B0x44/0xae RIP: 0033:0x7f66c882ce99 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 \u003C48\u003E 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f66c71a2168 EFLAGS: 00000246 ORIG_RAX: 0000000000000110 RAX: ffffffffffffffda RBX: 00007f66c893ff60 RCX: 00007f66c882ce99 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000048040200 RBP: 00007f66c8886ff1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fff6634832f R14: 00007f66c71a2300 R15: 0000000000022000  \u003C/TASK\u003E",
  "published": "2024-06-19T15:15:53Z",
  "severity": "medium",
  "cvss": 5.5,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
  "epss": 0.00263,
  "epssPercentile": 0.18223,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "5.15.15-1",
      "fix": "DEBIAN-CVE-2021-47588",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47588",
      "released": "2024-06-19T15:15:53Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "5.15.15-1",
      "fix": "DEBIAN-CVE-2021-47588",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47588",
      "released": "2024-06-19T15:15:53Z"
    },
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "5.15.15-1",
      "fix": "DEBIAN-CVE-2021-47588",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-47588",
      "released": "2024-06-19T15:15:53Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-09T01:18:40Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}