CVE catalog

CVE-2026-50560

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty HTTP/2 max header size handling produces an attack sim

[CVE catalog]

Severity
Medium · CVSS 6.9
Published
Source
[NVD] · [CVE record]
EPSS
0.40% · Oct 25, 2026

Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty HTTP/2 max header size handling produces an attack similar to HTTP/2 Rapid Reset. There is a setting in the http2 specification called `SETTINGS_MAX_HEADER_LIST_SIZE`. When a client sends that setting to Netty, it appears that Netty will behave as follows: read the request; proxy the request to the origin; attempt to produce a response; and create an exception while writing the headers for the response. Functionally, this should be similar to the http2 reset attack, but with a different on-the-wire signature. Versions 4.1.135.Final and 4.2.15.Final patch the issue.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

DistributionPackageReleaseVersionStatus
Debiannettysid1:4.1.48-16vulnerable
Debiannettyforky1:4.1.48-16vulnerable
Debiannettytrixie1:4.1.48-10+deb13u1vulnerable
Debiannettytrixie-security1:4.1.48-10+deb13u1vulnerable
Debiannettybookworm1:4.1.48-7+deb12u2vulnerable
Debiannettybookworm-security1:4.1.48-7+deb12u2vulnerable
CpenettyNot reportedNot reportedvulnerable
CpenettyNot reported4.1.135fixed
CpenettyNot reported4.2.15fixed

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Debiannettysourcesid(unfixed)not yet assignedNot reported[1139914]
Debiannettysourceforky(unfixed)not yet assignedNot reported[1139914]
Debiannettysourcetrixie(unfixed)not yet assignedNot reported[1139914]
Debiannettysourcebookworm(unfixed)not yet assignedNot reported[1139914]
CpenettycpeNot reported4.1.135Not reportedNot reportedNot reported
CpenettycpeNot reported4.2.15Not reportedNot reportedNot reported

[Debian bug #1139914]

OpenFactory catalog packages

[Debian 12 (Bookworm)]

  • [libnetty-java]Affected

    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]Affected

    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] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]