CVE-2025-61926

high

Description

Allstar is a GitHub App to set and enforce security policies. In versions prior to 4.5, a vulnerability in Allstar’s Reviewbot component caused inbound webhook requests to be validated against a hard-coded, shared secret. The value used for the secret token was compiled into the Allstar binary and could not be configured at runtime. In practice, this meant that every deployment using Reviewbot would validate requests with the same secret unless the operator modified source code and rebuilt the component - an expectation that is not documented and is easy to miss. All Allstar releases prior to v4.5 that include the Reviewbot code path are affected. Deployments on v4.5 and later are not affected. Those who have not enabled or exposed the Reviewbot endpoint are not exposed to this issue.

References

https://github.com/ossf/allstar/security/advisories/GHSA-33f4-mjch-7fpr

https://github.com/ossf/allstar/pull/713

https://github.com/ossf/allstar/commit/e004ecb540d63ca6f5b1689b41af6c0040a82c73

https://github.com/ossf/allstar/blob/294ae985cc2facd0918e8d820e4196021aa0b914/pkg/reviewbot/reviewbot.go#L59

Details

Source: Mitre, NVD

Published: 2025-10-09

Updated: 2026-04-15

Risk Information

CVSS v2

Base Score: 7.5

Vector: CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P

Severity: High

CVSS v3

Base Score: 9.8

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Severity: Critical

CVSS v4

Base Score: 8.2

Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

Severity: High

EPSS

EPSS: 0.00041