CVE catalog

CVE-2026-59898

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by

[CVE catalog]

Severity
Medium · CVSS 6.3
Published
Source
[NVD] · [CVE record]
EPSS
0.44% · Oct 25, 2026

Netty is an asynchronous, event-driven network application framework. Prior to versions 4.1.136.Final and 4.2.16.Final, ab attacker can force WebSocket upgrade via the lax V07 (or V08) handshaker by sending `Sec-WebSocket-Version: 7` and omitting `Connection: Upgrade` / `Upgrade: websocket` headers, completing a protocol switch that a proxy would not recognize as an Upgrade request and enabling HTTP request smuggling / protocol-confusion attacks. This issue has been fixed in versions 4.1.136.Final and 4.2.16.Final.

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
Mavenio.netty:netty-codec-httpNot reported4.2.16.Finalfixed
Mavenio.netty:netty-codec-httpNot reported4.1.136.Finalfixed

Fixed-version evidence

DistributionPackageTypeReleaseFixed versionUrgencyOriginBugs
Debiannettysourcesid(unfixed)not yet assignedNot reported[1143052]
Debiannettysourceforky(unfixed)not yet assignedNot reported[1143052]
Debiannettysourcetrixie(unfixed)not yet assignedNot reported[1143052]
Debiannettysourcebookworm(unfixed)not yet assignedNot reported[1143052]
Mavenio.netty:netty-codec-httpmavenNot reported4.2.16.FinalNot reportedNot reportedNot reported
Mavenio.netty:netty-codec-httpmavenNot reported4.1.136.FinalNot reportedNot reportedNot reported

[Debian bug #1143052]

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