CVE-2026-56865
Published: August 18, 2026Last modified: August 26, 2026
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
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 8.4 |
| Attack Vector | LOCAL |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | HIGH |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | go | Fixed (1.25.14-r0) |
| 25 LTS | go | Fixed (1.25.14-r0) | |
| Stream | go | Fixed (1.26.7-r0) | |
| Hardened Containers | 23 LTS | go | Fixed (1.25.14-r0) |
| 25 LTS | go | Fixed (1.25.14-r0) | |
| Stream | go | Fixed (1.26.7-r0) |