GO-2026-6179
Fix transparency log tile verification bypass in golang.org/x/mod/sumdb/tlog
At a glance
- Published
- Updated
- CVE
- CVE-2026-56865
- Aliases
- BIT-golang-2026-56865
Description
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 | Versions |
|---|---|
| Go · toolchain | introduced 0, fixed 1.25.13, introduced 1.26.0-0, fixed 1.26.6, introduced 1.27.0-0, fixed 1.27.0-rc.3 |
| Go · golang.org/x/mod | introduced 0, fixed 0.40.0 |
References
- https://go.dev/issue/80744 REPORT
- https://groups.google.com/g/golang-announce/c/94pEornpRlI WEB
- https://go.dev/cl/814960 FIX
- https://go.dev/cl/815020 FIX
Sources
| Source | Licence |
|---|---|
| OSV.dev | CC-BY 4.0 — Go Vulnerability Database |