---
id: CVE-2022-42966
aliases:
  - GHSA-2p9h-ccw7-33gf
  - PYSEC-2022-43178
title: cleo is vulnerable to Regular Expression Denial of Service (ReDoS)
summary: cleo is vulnerable to Regular Expression Denial of Service (ReDoS)
severity: medium
cvss: 5.9
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'
vendor: cleo
product: cleo
ecosystem: pip
affected:
  - 'cleo >= 1.0.0a1, < 2.0.0'
patched:
  - cleo 2.0.0
published: '2022-11-10'
updated: '2026-07-02'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-2p9h-ccw7-33gf'
references:
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2022-42966'
  - url: 'https://github.com/python-poetry/cleo/pull/285'
  - url: >-
      https://github.com/python-poetry/cleo/commit/b5b9a04d2caf58bf7cf94eb7ae4a1ebbe60ea455
  - url: 'https://github.com/advisories/GHSA-2p9h-ccw7-33gf'
  - url: >-
      https://github.com/pypa/advisory-database/tree/main/vulns/cleo/PYSEC-2022-43178.yaml
  - url: 'https://github.com/python-poetry/cleo'
  - url: 'https://github.com/python-poetry/cleo/releases/tag/2.0.0'
  - url: 'https://research.jfrog.com/vulnerabilities/cleo-redos-xray-257186'
tags:
  - osv
  - pip
epss: 0.00953
epssPercentile: 0.5965
ingestedAt: '2026-07-08T18:25:44.584Z'
---

## Overview

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.

## Affected packages

- `cleo >= 1.0.0a1, < 2.0.0`

## Remediation

Upgrade to a patched release:

- `cleo 2.0.0`