GHSA-4mp9-239f-g9hg

    Dashboard / Vulnerabilities / GHSA-4mp9-239f-g9hg

    GHSA-4mp9-239f-g9hg

    Published: 22 Jul 2026Last Modified: 10 Sept 2026

    Summary: Netty: WebSockets V07/V08 handshaker missing Connection/Upgrade validation

    Details: ## Summary An 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.

    References: https://github.com/netty/netty/security/advisories/GHSA-4mp9-239f-g9hg, https://github.com/netty/netty, https://github.com/netty/netty/releases/tag/netty-4.1.136.Final, https://github.com/netty/netty/releases/tag/netty-4.2.16.Final

    Affected packages

    Package

    Name: io.netty:netty-codec-http

    Purl: pkg:maven/io.netty/netty-codec-http

    Affected ranges

    Type: ECOSYSTEM

    Events:

    Introduced- 4.2.0.Final
    Fixed -4.2.16.Final

    Affected versions

    4.2.0.Final
    4.2.1.Final
    4.2.10.Final
    4.2.11.Final
    4.2.12.Final
    4.2.13.Final
    4.2.14.Final
    4.2.15.Final
    4.2.2.Final
    4.2.3.Final
    4.2.4.Final
    4.2.5.Final
    4.2.6.Final
    4.2.7.Final
    4.2.8.Final
    4.2.9.Final

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High