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  5. CVE-2021-3842

CVE-2021-3842: NLTK Vulnerable to REDoS

January 6, 2022 (updated September 26, 2024)

NLTK is vulnerable to REDoS in some RegexpTaggers used in the functions get_pos_tagger and malt_regex_tagger.

References

  • github.com/advisories/GHSA-rqjh-jp2r-59cj
  • github.com/nltk/nltk
  • github.com/nltk/nltk/commit/2a50a3edc9d35f57ae42a921c621edc160877f4d
  • github.com/nltk/nltk/pull/2906
  • github.com/pypa/advisory-database/tree/main/vulns/nltk/PYSEC-2022-5.yaml
  • huntr.dev/bounties/761a761e-2be2-430a-8d92-6f74ffe9866a
  • nvd.nist.gov/vuln/detail/CVE-2021-3842

Code Behaviors & Features

Detect and mitigate CVE-2021-3842 with GitLab Dependency Scanning

Secure your software supply chain by verifying that all open source dependencies used in your projects contain no disclosed vulnerabilities. Dependency Scanning using SBOM also detects vulnerabilities from proprietary advisories that this site does not include. Learn more about Dependency Scanning using SBOM →

Affected versions

All versions before 3.6.6

Fixed versions

  • 3.6.6

Solution

Upgrade to version 3.6.6 or above.

Impact 7.5 HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Learn more about CVSS

Weakness

  • CWE-1333: Inefficient Regular Expression Complexity

Source file

pypi/nltk/CVE-2021-3842.yml

Spotted a mistake? Edit the file on GitLab.

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