# CVE-2026-34938: PraisonAI: Python Sandbox Escape via str Subclass startswith() Override in execute_code

> Attackers can bypass the Python sandbox in PraisonAI to execute arbitrary OS commands on the host by exploiting a flaw in the execute_code function.

- **Severity:** Critical 10.0 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/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:** 3 Apr 2026
- **Updated:** 6 Apr 2026
- **Also known as:** GHSA-6vh2-h83c-9294, PYSEC-2026-484

## What is CVE-2026-34938?

CVE-2026-34938 is a critical code injection vulnerability in MervinPraison PraisonAI, published on 3 Apr 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 1.5.90, execute_code() in praisonai-agents runs attacker-controlled Python inside a three-layer sandbox that can be fully bypassed by passing a str subclass with an overridden startswith() method to the _safe_getattr wrapper, achieving arbitrary OS command execution on the host. This issue has been patched in version 1.5.90.

Weakness: CWE-693 (Protection Mechanism Failure)

## Which versions are affected by CVE-2026-34938?

3 open source packages ship an affected version, including praisonaiagents. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `praisonaiagents` | PyPI | All versions | 1.5.90 |
| `praisonaiagents` | PyPI | All versions | 1.5.90 |
| `praisonaiagents` | PyPI | All versions | 1.5.90 |

Products: Praison Praisonaiagents.

## How do I fix CVE-2026-34938?

Upgrade praisonaiagents to 1.5.90 or later.

## Is CVE-2026-34938 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-34938 exists.

## Other vulnerabilities in MervinPraison PraisonAI

- [CVE-2026-40111](https://insights.sbomify.com/CVE-2026-40111/): PraisonAIAgents has an OS Command Injection via shell=True in Memory Hooks Executor (memory/hooks.py) (critical 9.3)
- [CVE-2026-34954](https://insights.sbomify.com/CVE-2026-34954/): PraisonAI: SSRF in FileTools.download_file() via Unvalidated URL (high 8.6)
- [CVE-2026-34937](https://insights.sbomify.com/CVE-2026-34937/): PraisonAI: Shell Injection in run_python() via Unescaped $() Substitution (high 7.8)
- [CVE-2026-44335](https://insights.sbomify.com/CVE-2026-44335/): SSRF bypass in PraisonAI (high 7.7)
- [CVE-2026-40150](https://insights.sbomify.com/CVE-2026-40150/): PraisonAIAgents has SSRF and Local File Read via Unvalidated URLs in web_crawl Tool (high 7.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-34938 and fix it if it is affected.

What it is: CVE-2026-34938 is a critical code injection vulnerability in MervinPraison PraisonAI, published on 3 Apr 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-2026-34938 exists.

Affected packages and fixed versions:
- praisonaiagents (PyPI): affected all versions; fixed in 1.5.90
- praisonaiagents (PyPI): affected all versions; fixed in 1.5.90
- praisonaiagents (PyPI): affected all versions; fixed in 1.5.90

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-2026-34938/ (Markdown: https://insights.sbomify.com/CVE-2026-34938/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-34938
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-34938
- OSV: https://osv.dev/vulnerability/CVE-2026-34938

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-34938/
Summaries are generated and may contain mistakes; the official description above is the record.