# CVE-2026-47391: PraisonAI's unauthenticated A2A official example can reach real LLM-driven `eval()` tool execution

> Unauthenticated attackers can execute arbitrary Python code via the A2A example's eval-based tool, requiring an upgrade to secure the deployment.

- **Severity:** Critical 9.8 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 21 Jul 2026
- **Updated:** 23 Jul 2026
- **Also known as:** GHSA-vg22-4gmj-prxw, PYSEC-2026-478

## What is CVE-2026-47391?

CVE-2026-47391 is a critical code injection vulnerability in MervinPraison PraisonAI, published on 21 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

PraisonAI is a multi-agent teams system. Prior to version 4.6.40, PraisonAI's first-party A2A server example exposes an unauthenticated A2A JSON-RPC endpoint and registers a `calculate(expression)` tool implemented with Python `eval()`. The example also binds to `0.0.0.0`. A remote unauthenticated attacker can send `message/send` to `/a2a`; the request reaches `agent.chat()`, and a real LLM can invoke the registered `calculate` tool. In testing with `gemini/gemini-2.5-flash-lite`, this resulted in arbitrary Python execution in the server process, confirmed by creation of a marker file from an unauthenticated HTTP request. The issue affects deployments following the official A2A example or similar unauthenticated public A2A deployments with unsafe tools. The default unauthenticated A2A surface also exposes task history and task cancellation APIs, increasing confidentiality and integrity impact. Version 4.6.40 patches the issue.

Weakness: CWE-95 (Improper Neutralization of Directives in Dynamically Evaluated Code), CWE-306 (Missing Authentication for Critical Functionality)

## Which versions are affected by CVE-2026-47391?

3 open source packages ship an affected version, including praisonai and PraisonAI.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `praisonai` | PyPI | All versions | 4.6.40 |
| `praisonai` | PyPI | All versions | 4.6.40 |
| `PraisonAI` | PyPI | All versions | 4.6.40 |

## How do I fix CVE-2026-47391?

Upgrade praisonai to 4.6.40 or later.

## Is CVE-2026-47391 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47391 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-47391 and fix it if it is affected.

What it is: CVE-2026-47391 is a critical code injection vulnerability in MervinPraison PraisonAI, published on 21 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-47391 exists.

Affected packages and fixed versions:
- praisonai (PyPI): affected all versions; fixed in 4.6.40
- praisonai (PyPI): affected all versions; fixed in 4.6.40
- PraisonAI (PyPI): affected all versions; fixed in 4.6.40

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-2026-47391/ (Markdown: https://insights.sbomify.com/CVE-2026-47391/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-47391
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-47391
- OSV: https://osv.dev/vulnerability/CVE-2026-47391

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-47391/
Summaries are generated and may contain mistakes; the official description above is the record.