# CVE-2026-59960: Argos JavaScript: CI Branch Name OS Command Injection in @argos-ci/core

> Attackers can execute arbitrary commands on CI runners via shell metacharacters in branch names, potentially exposing secrets or compromising the build environment.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 14 Sep 2026
- **Updated:** 14 Sep 2026
- **Also known as:** GHSA-4x45-gxvp-6283

## What is CVE-2026-59960?

CVE-2026-59960 is a high-severity command injection vulnerability in argos-ci argos-javascript, published on 14 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Argos JavaScript provides official Argos SDKs for JavaScript. Prior to Argos core package version 6.2.1, attacker-controlled CI branch or ref values from GITHUB_HEAD_REF or ARGOS_BRANCH can flow through config.branch and getMergeBaseCommitSha() when hasRemoteContentAccess is false. The gitFetch() and gitMergeBase() functions in packages/core/src/ci-environment/git.ts interpolate these values into execSync() command strings executed by /bin/sh -c, so shell metacharacters in a pull-request branch name can execute arbitrary commands with the Argos upload process privileges on the CI runner. Successful exploitation can expose CI secrets, alter build artifacts, or compromise the runner. This issue is fixed in Argos core package version 6.2.1.

Weakness: CWE-78 (Improper Neutralization of Special Elements used in an OS Command)

## Which versions are affected by CVE-2026-59960?

2 open source packages ship an affected version, including @argos-ci/core.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `@argos-ci/core` | npm | All versions | 6.2.1 |
| `@argos-ci/core` | npm | All versions | 6.2.1 |

## How do I fix CVE-2026-59960?

Upgrade @argos-ci/core to 6.2.1 or later.

## Is CVE-2026-59960 being exploited?

There is no known exploitation of CVE-2026-59960 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-59960 and fix it if it is affected.

What it is: CVE-2026-59960 is a high-severity command injection vulnerability in argos-ci argos-javascript, published on 14 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-59960 in the wild and no public exploit code.

Affected packages and fixed versions:
- @argos-ci/core (npm): affected all versions; fixed in 6.2.1
- @argos-ci/core (npm): affected all versions; fixed in 6.2.1

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-59960/ (Markdown: https://insights.sbomify.com/CVE-2026-59960/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-59960
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-59960
- OSV: https://osv.dev/vulnerability/CVE-2026-59960

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-59960/
Summaries are generated and may contain mistakes; the official description above is the record.