critical9.8
CVE-2026-34041
act: Unrestricted set-env and add-path command processing enables environment injection
Impact
act is a project which allows for local running of github actions. Prior to version 0.2.86, act unconditionally processes the deprecated ::set-env:: and ::add-path:: workflow commands, which was disabled due to environment injection risks. When a workflow step echoes untrusted data to stdout, an attacker can inject these commands to set arbitrary environment variables or modify the PATH for all subsequent steps in the job. This issue has been patched in version 0.2.86.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| go | github.com/nektos/act | <= 0.2.85 | 0.2.86 |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Nektos | Act | before 0.2.86 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-xmgr-9pqc-h5vw
- https://github.com/nektos/act/security/advisories/GHSA-xmgr-9pqc-h5vw
- https://github.com/nektos/act/commit/0c739c8e39c41aa5a07665f732da9cab6df0097a
- https://github.com/advisories/GHSA-mfwh-5m23-j46w
- https://github.com/nektos/act/releases/tag/v0.2.86
- https://nvd.nist.gov/vuln/detail/CVE-2026-34041