# CVE-2026-27961: Agenta's Server-Side Template Injection (SSTI) via custom evaluator Jinja2 templates allows RCE

> Attacker can achieve remote code execution via Server-Side Template Injection in Agenta's evaluator templates, affecting self-hosted deployments.

- **Severity:** High 8.8 (`CVSS:3.1/AV:N/AC:L/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:** 26 Feb 2026
- **Updated:** 26 Feb 2026
- **Also known as:** GHSA-cfr2-mp74-3763, PYSEC-2026-7

## What is CVE-2026-27961?

CVE-2026-27961 is a high-severity code injection vulnerability in Agenta-AI agenta, published on 26 Feb 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Agenta is an open-source LLMOps platform. A Server-Side Template Injection (SSTI) vulnerability exists in versions prior to 0.86.8 in Agenta's API server evaluator template rendering. Although the vulnerable code lives in the SDK package, it is executed server-side within the API process when running evaluators. This does not affect standalone SDK usage — it only impacts self-hosted or managed Agenta platform deployments. Version 0.86.8 contains a fix for the issue.

Weakness: CWE-1336 (Improper Neutralization of Special Elements Used in a Template Engine)

## Which versions are affected by CVE-2026-27961?

1 open source package ship an affected version, including agenta. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `agenta` | PyPI | All versions | 0.86.8 |

Products: Agentatech Agenta.

## How do I fix CVE-2026-27961?

Upgrade agenta to 0.86.8 or later.

## Is CVE-2026-27961 being exploited?

There is no known exploitation of CVE-2026-27961 in the wild and no public exploit code.

## Other vulnerabilities in Agenta-AI agenta

- [CVE-2026-27952](https://insights.sbomify.com/CVE-2026-27952/): Agenta has Python Sandbox Escape, Leading to Remote Code Execution (RCE) (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-27961 and fix it if it is affected.

What it is: CVE-2026-27961 is a high-severity code injection vulnerability in Agenta-AI agenta, published on 26 Feb 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-2026-27961 in the wild and no public exploit code.

Affected packages and fixed versions:
- agenta (PyPI): affected all versions; fixed in 0.86.8

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-2026-27961/ (Markdown: https://insights.sbomify.com/CVE-2026-27961/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-27961
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-27961
- OSV: https://osv.dev/vulnerability/CVE-2026-27961

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-27961/
Summaries are generated and may contain mistakes; the official description above is the record.