GO-2026-6179

    Dashboard / Vulnerabilities / GO-2026-6179

    GO-2026-6179

    Published: 13 Aug 2026Last Modified: 19 Aug 2026

    Summary: Fix transparency log tile verification bypass in golang.org/x/mod/sumdb/tlog

    Details: A malicious GOPROXY was previously capable of forging up to two sumdb tiles that allow for a requested module to bypass the GOSUMDB check and persist attacker-controlled module content to a local Go module cache. This attack allows for a malicious GOPROXY to serve malicious module content that cannot be detected by evaluating the transparency log. All tiles are now correctly verified against their parents. In order to determine if you have been affected: rm -r go.sum go.work.sum vendor/ && go mod tidy

    Affected packages

    Package

    Name: toolchain

    Purl: pkg:golang/toolchain

    Affected ranges

    Type: SEMVER

    Events:

    Introduced- 0
    Fixed -1.25.13

    Affected versions

    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