{
  "cveId": "CVE-2021-43797",
  "url": "https://patchblox.com/security/cve/CVE-2021-43797",
  "summary": "CVE-2021-43797 is fixed in 3 products on 1 platform, first by DEBIAN-CVE-2021-43797, released December 9, 2021. It is not reported as exploited. Patch Radar priority: Routine.",
  "title": "libnetty-java: Netty is an asynchronous event-driven network application framework forrapid development of maintainable high perform...",
  "description": "Netty is an asynchronous event-driven network application framework forrapid development of maintainable high performance protocol servers \u0026clients. Netty prior to version 4.1.71.Final skips control chars when theyare present at the beginning / end of the header name. It should insteadfail fast as these are not allowed by the spec and could lead to HTTPrequest smuggling. Failing to do the validation might cause netty to\u0022sanitize\u0022 header names before it forward these to another remote systemwhen used as proxy. This remote system can\u0027t see the invalid usage anymore,and therefore does not do the validation itself. Users should upgrade toversion 4.1.71.Final.",
  "published": "2021-12-09T11:15:00Z",
  "severity": "Medium",
  "cvss": 6.5,
  "cvssVector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N",
  "epss": 0.02884,
  "epssPercentile": 0.86947,
  "priority": "Routine",
  "priorityTier": 4,
  "exploited": false,
  "vendorExploited": false,
  "disclosed": false,
  "fixes": [
    {
      "platform": "linux",
      "product": "libdb",
      "release": "rocky 8",
      "fixedVersion": "0:5.3.28-42.el8_4",
      "fix": "RLSA-2022:5498",
      "url": "https://patchblox.com/security/fix/linux/rlsa-2022-5498",
      "released": "2022-07-05T13:55:16Z"
    },
    {
      "platform": "linux",
      "product": "libnetty-java",
      "release": "Ubuntu 18.04.6 LTS (bionic)",
      "fixedVersion": "1:4.1.7-4ubuntu0.1\u002Besm2",
      "fix": "libnetty-java 1:4.1.7-4ubuntu0.1\u002Besm2",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-bionic-libnetty-java-1-4.1.7-4ubuntu0.1-esm2",
      "released": "2022-12-12T23:15:00Z"
    },
    {
      "platform": "linux",
      "product": "libnetty-java",
      "release": "Ubuntu 20.04 LTS (focal)",
      "fixedVersion": "1:4.1.45-1ubuntu0.1~esm1",
      "fix": "libnetty-java 1:4.1.45-1ubuntu0.1~esm1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-focal-libnetty-java-1-4.1.45-1ubuntu0.1-esm1",
      "released": "2022-12-12T23:15:00Z"
    },
    {
      "platform": "linux",
      "product": "libnetty-java",
      "release": "Ubuntu 22.04.1 LTS (jammy)",
      "fixedVersion": "1:4.1.48-4\u002Bdeb11u1build0.22.04.1",
      "fix": "libnetty-java 1:4.1.48-4\u002Bdeb11u1build0.22.04.1",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-jammy-libnetty-java-1-4.1.48-4-deb11u1build0.22.04.1",
      "released": "2022-12-12T23:15:00Z"
    },
    {
      "platform": "linux",
      "product": "libnetty-java",
      "release": "Ubuntu 24.10 (oracular)",
      "fixedVersion": "4.1.48-6",
      "fix": "libnetty-java 4.1.48-6",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-oracular-libnetty-java-4.1.48-6",
      "released": "2026-01-16T01:42:22Z"
    },
    {
      "platform": "linux",
      "product": "libnetty-java",
      "release": "Ubuntu 25.04 (plucky)",
      "fixedVersion": "4.1.48-6",
      "fix": "libnetty-java 4.1.48-6",
      "url": "https://patchblox.com/security/fix/linux/ubuntu-plucky-libnetty-java-4.1.48-6",
      "released": "2026-01-16T01:42:24Z"
    },
    {
      "platform": "linux",
      "product": "netty",
      "release": "Debian 12.15 (bookworm)",
      "fixedVersion": "1:4.1.48-6",
      "fix": "DEBIAN-CVE-2021-43797",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-43797",
      "released": "2021-12-09T19:15:07Z"
    },
    {
      "platform": "linux",
      "product": "netty",
      "release": "Debian 13.5 (trixie)",
      "fixedVersion": "1:4.1.48-6",
      "fix": "DEBIAN-CVE-2021-43797",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-43797",
      "released": "2021-12-09T19:15:07Z"
    },
    {
      "platform": "linux",
      "product": "netty",
      "release": "Debian 14",
      "fixedVersion": "1:4.1.48-6",
      "fix": "DEBIAN-CVE-2021-43797",
      "url": "https://patchblox.com/security/fix/linux/debian-cve-2021-43797",
      "released": "2021-12-09T19:15:07Z"
    }
  ],
  "noFixYet": [],
  "dataAsOf": "2026-11-08T13:06:02Z",
  "attribution": {
    "text": "Data: Patchblox Patch Radar",
    "url": "https://patchblox.com/security/patch-radar",
    "terms": "https://patchblox.com/security/patch-radar/use-the-data"
  }
}