CVE catalog

CVE-2026-55833

Netty is a network application framework for…

[CVE catalog]

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty SPDY header decoding continues inflating zlib-compressed header blocks after the raw header parser has exceeded `maxHeaderSize` and marked the frame truncated in `SpdyFrameCodec`, allowing a remote peer to send a small compressed `HEADERS` block that expands into much larger raw header data and causes compression-amplified CPU and allocation churn. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

Severity
High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
Source
[NVD] · [CVE record]
EPSS
0.66% · Oct 27, 2026

Projects and upstream resources

Reported versions and fixes

Each observation applies to its named package, distribution, and release. Distribution backports can fix a vulnerability while retaining an older upstream version number.

Version impact has not been established. The original provider fields are retained below.

Provider details and historical evidence
Original provider fields
{
  "package_releases": [
    {
      "name": "netty",
      "status": "vulnerable",
      "release": "sid",
      "version": "1:4.1.48-16"
    },
    {
      "name": "netty",
      "status": "vulnerable",
      "release": "forky",
      "version": "1:4.1.48-16"
    },
    {
      "name": "netty",
      "status": "vulnerable",
      "release": "trixie",
      "version": "1:4.1.48-10+deb13u1"
    },
    {
      "name": "netty",
      "status": "vulnerable",
      "release": "trixie-security",
      "version": "1:4.1.48-10+deb13u1"
    },
    {
      "name": "netty",
      "status": "vulnerable",
      "release": "bookworm",
      "version": "1:4.1.48-7+deb12u2"
    },
    {
      "name": "netty",
      "status": "vulnerable",
      "release": "bookworm-security",
      "version": "1:4.1.48-7+deb12u2"
    }
  ],
  "fixed_versions": [
    {
      "bug": 1142680,
      "name": "netty",
      "type": "source",
      "origin": null,
      "release": "sid",
      "urgency": "not yet assigned",
      "fixed_version": ""
    },
    {
      "bug": 1142680,
      "name": "netty",
      "type": "source",
      "origin": null,
      "release": "forky",
      "urgency": "not yet assigned",
      "fixed_version": ""
    },
    {
      "bug": 1142680,
      "name": "netty",
      "type": "source",
      "origin": null,
      "release": "trixie",
      "urgency": "not yet assigned",
      "fixed_version": ""
    },
    {
      "bug": 1142680,
      "name": "netty",
      "type": "source",
      "origin": null,
      "release": "bookworm",
      "urgency": "not yet assigned",
      "fixed_version": ""
    }
  ],
  "distribution_packages": [
    {
      "name": "netty",
      "ecosystem": "cpe",
      "fixed_version": "not yet fixed"
    },
    {
      "name": "io.netty:netty-codec-http",
      "ecosystem": "maven",
      "fixed_version": "4.2.16.Final"
    },
    {
      "name": "io.netty:netty-codec-http",
      "ecosystem": "maven",
      "fixed_version": "4.1.136.Final"
    }
  ]
}

[Debian bug #1142680]

OpenFactory catalog packages

Matching against OpenFactory catalog package versions is in progress.

[Debian 12 (Bookworm)]

  • [libnetty-java]Unknown

    Source package: [netty]

    Details (4)

    • 1:4.1.48-7+deb12u2 · all · bookworm

      Affected

      nvd · netty · debian · bookworm; nvd · netty · debian · 12

    • 1:4.1.48-7+deb12u2 · all · bookworm

      Affected

      nvd · netty · debian · bookworm; nvd · netty · debian · 12

    • 1:4.1.48-7+deb12u2 · all · bookworm-security

      Affected

      nvd · netty · debian · bookworm; nvd · netty · debian · 12

    • 1:4.1.48-7+deb12u2 · all · bookworm-security

      Affected

      nvd · netty · debian · bookworm; nvd · netty · debian · 12

[Debian 13 (Trixie)]

  • [libnetty-java]Unknown

    Source package: [netty]

    Details (4)

    • 1:4.1.48-10+deb13u1 · all · trixie

      Affected

      nvd · netty · debian · 13

    • 1:4.1.48-10+deb13u1 · all · trixie

      Affected

      nvd · netty · debian · 13

    • 1:4.1.48-10+deb13u1 · all · trixie-security

      Affected

      nvd · netty · debian · 13

    • 1:4.1.48-10+deb13u1 · all · trixie-security

      Affected

      nvd · netty · debian · 13

Observed:

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [GitHub Advisory Database] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]