{
  "cveId": "CVE-2026-27624",
  "url": "https://patchblox.com/security/cve/CVE-2026-27624",
  "summary": "CVE-2026-27624 is fixed in coturn on 1 platform, first by DEBIAN-CVE-2026-27624, released February 25, 2026. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "coturn: Coturn is a free open source implementation of TURN and STUN Server",
  "description": "Coturn is a free open source implementation of TURN and STUN Server. Coturn is commonly configured to block loopback and internal ranges using \u0022denied-peer-ip\u0022 and/or default loopback restrictions. CVE-2020-26262 addressed bypasses involving \u00220.0.0.0\u0022, \u0022[::1]\u0022 and \u0022[::]\u0022, but IPv4-mapped IPv6 is not covered. When sending a \u0022CreatePermission\u0022 or \u0022ChannelBind\u0022 request with the \u0022XOR-PEER-ADDRESS\u0022 value of \u0022::ffff:127.0.0.1\u0022, a successful response is received, even though \u0022127.0.0.0/8\u0022 is blocked via \u0022denied-peer-ip\u0022. The root cause is that, prior to the updated fix implemented in version 4.9.0, three functions in \u0022src/client/ns_turn_ioaddr.c\u0022 do not check \u0022IN6_IS_ADDR_V4MAPPED\u0022. \u0022ioa_addr_is_loopback()\u0022 checks \u0022127.x.x.x\u0022 (AF_INET) and \u0022::1\u0022 (AF_INET6), but not \u0022::ffff:127.0.0.1.\u0022 \u0022ioa_addr_is_zero()\u0022 checks \u00220.0.0.0\u0022 and \u0022::\u0022, but not \u0022::ffff:0.0.0.0.\u0022 \u0022addr_less_eq()\u0022 used by \u0022ioa_addr_in_range()\u0022 for \u0022denied-peer-ip\u0022 matching: when the range is AF_INET and the peer is AF_INET6, the comparison returns 0 without extracting the embedded IPv4. Version 4.9.0 contains an updated fix to address the bypass of the fix for CVE-2020-26262.",
  "published": "2026-02-25T05:17:25Z",
  "severity": "medium",
  "cvss": 6.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N",
  "epss": 0.00345,
  "epssPercentile": 0.28289,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "coturn",
      "release": "Debian 14",
      "fixedVersion": "4.12.0-1",
      "fix": "DEBIAN-CVE-2026-27624",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-27624",
      "released": "2026-02-25T05:17:25Z"
    },
    {
      "platform": "linux",
      "product": "coturn",
      "release": "opensuse-leap 16.0",
      "fixedVersion": "4.14.0-bp160.1.1",
      "fix": "OPENSUSE-SU-2026:21184-1",
      "url": "https://patchblox.com/security/fix/linux/opensuse-su-2026-21184-1",
      "released": "2026-06-30T11:31:41Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T19:12:23Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}