Vulnerability · Published Apr 7, 2026 · Assigned by GitHub_M
CVE-2026-35580Emissary has GitHub Actions Shell Injection via Workflow Inputs
Critical 9.1
In plain English
A critical-severity command injection in emissary from NationalSecurityAgency. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code. Fixed versions are available - upgrade the affected package.
Official description
Emissary is a P2P based data-driven workflow engine. Prior to 8.39.0, GitHub Actions workflow files contained shell injection points where user-controlled workflow_dispatch inputs were interpolated directly into shell commands via ${{ }} expression syntax. An attacker with repository write access could inject arbitrary shell commands, leading to repository poisoning and supply chain compromise affecting all downstream users. This vulnerability is fixed in 8.39.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Maven | gov.nsa.emissary:emissary | 8.39.0 | GHSA-3g6g-gq4r-xjm9 |
| Ubuntu:25.10 | botan3 | no fix listed | UBUNTU-CVE-2026-35580 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| NationalSecurityAgency | emissary | < 8.39.0 |
Weakness: CWE-77 · Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
References
- https://github.com/NationalSecurityAgency/emissary/security/advisories/GHSA-3g6g-gq4r-xjm9 x_refsource_CONFIRM
- https://github.com/NationalSecurityAgency/emissary/pull/1286 x_refsource_MISC
- https://github.com/NationalSecurityAgency/emissary/pull/1288 x_refsource_MISC