CVE-2026-34041
act: Unrestricted set-env and add-path command processing enables environment injection
Description
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.
INFO
Published Date :
March 31, 2026, 3:15 a.m.
Last Modified :
April 6, 2026, 3:34 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | ||||
| CVSS 4.0 | HIGH | [email protected] |
Solution
- Update act to version 0.2.86 or later.
- Avoid processing untrusted data in workflow steps.
- Sanitize all user-provided input in workflows.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-34041.
| URL | Resource |
|---|---|
| https://github.com/nektos/act/commit/0c739c8e39c41aa5a07665f732da9cab6df0097a | Patch |
| https://github.com/nektos/act/releases/tag/v0.2.86 | Product |
| https://github.com/nektos/act/security/advisories/GHSA-xmgr-9pqc-h5vw | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-34041 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-34041
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-34041 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-34041 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Apr. 06, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:nektos:act:*:*:*:*:*:*:*:* versions up to (excluding) 0.2.86 Added Reference Type GitHub, Inc.: https://github.com/nektos/act/commit/0c739c8e39c41aa5a07665f732da9cab6df0097a Types: Patch Added Reference Type GitHub, Inc.: https://github.com/nektos/act/releases/tag/v0.2.86 Types: Product Added Reference Type GitHub, Inc.: https://github.com/nektos/act/security/advisories/GHSA-xmgr-9pqc-h5vw Types: Exploit, Mitigation, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Apr. 02, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H -
New CVE Received by [email protected]
Mar. 31, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 AV:N/AC:L/AT:P/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CWE CWE-74 Added Reference https://github.com/nektos/act/commit/0c739c8e39c41aa5a07665f732da9cab6df0097a Added Reference https://github.com/nektos/act/releases/tag/v0.2.86 Added Reference https://github.com/nektos/act/security/advisories/GHSA-xmgr-9pqc-h5vw