{
  "cveId": "CVE-2026-99042",
  "url": "https://patchblox.com/security/cve/CVE-2026-99042",
  "summary": "CVE-2026-99042 is fixed in linux on 1 platform by DEBIAN-CVE-2026-99042 (version 7.2.11-1), released October 24, 2026. It is not reported as exploited. Patch Radar priority: High.",
  "title": "linux: In the Linux kernel, the following vulnerability has been resolved:  io_uring/net: populate CONNECT filter fields for...",
  "description": "In the Linux kernel, the following vulnerability has been resolved:  io_uring/net: populate CONNECT filter fields for 24-byte sockaddr_in6  io_connect_bpf_populate() fills connect.port and connect.v6_addr for AF_INET6 only when addr_len \u003E= sizeof(struct sockaddr_in6), i.e. 28 bytes.  The IPv6 connect paths accept SIN6_LEN_RFC2133 (24 bytes), which already holds sin6_port and sin6_addr. io_connect() passes addr_len to the socket layer unchanged.  At addr_len 24 the filter sees family AF_INET6 with port and address zero, while the kernel connects to the real destination. A filter that denies an IPv6 port or address is bypassed. Denying connect.port == P rejects [::1]:P with -EACCES at addr_len 28 but connects at addr_len 24.  Use SIN6_LEN_RFC2133 as the threshold. sin6_scope_id stays zero when absent.  The threshold mismatch was found by an AI coding assistant (Claude Code) comparing this hook against the net/ipv6 length checks on my instructions; it also drafted the reproducer and this patch. I verified the bypass and the fix in a VM on 7.3-rc6 and that 7.2 has the same code.",
  "published": "2026-10-23T13:17:27Z",
  "severity": "high",
  "cvss": 8.4,
  "cvssVector": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:N",
  "epss": 0.0016,
  "epssPercentile": 0.05258,
  "priority": "High",
  "priorityTier": 3,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "linux",
      "release": "Debian 14",
      "fixedVersion": "7.2.11-1",
      "fix": "DEBIAN-CVE-2026-99042",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2026-99042",
      "released": "2026-10-24T13:25:57Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-12T01:51:14Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}