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  5. CVE-2016-9909

CVE-2016-9909: Improper Neutralization of Input During Web Page Generation in html5lib

May 17, 2022 (updated September 20, 2024)

The serializer in html5lib before 0.99999999 might allow remote attackers to conduct cross-site scripting (XSS) attacks by leveraging mishandling of the < (less than) character in attribute values.

References

  • github.com/advisories/GHSA-v9v9-xffq-rwr4
  • github.com/html5lib/html5lib-python
  • github.com/html5lib/html5lib-python/commit/9b8d8eb5afbc066b7fac9390f5ec75e5e8a7cab7
  • github.com/html5lib/html5lib-python/issues/11
  • github.com/html5lib/html5lib-python/issues/12
  • github.com/pypa/advisory-database/tree/main/vulns/html5lib/PYSEC-2017-14.yaml
  • html5lib.readthedocs.io/en/latest/changes.html
  • nvd.nist.gov/vuln/detail/CVE-2016-9909
  • web.archive.org/web/20161229134056/http://www.securityfocus.com/bid/95132

Code Behaviors & Features

Detect and mitigate CVE-2016-9909 with GitLab Dependency Scanning

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Affected versions

All versions before 0.999999999

Fixed versions

  • 0.999999999

Solution

Upgrade to version 0.999999999 or above.

Impact 6.1 MEDIUM

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Learn more about CVSS

Weakness

  • CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

Source file

pypi/html5lib/CVE-2016-9909.yml

Spotted a mistake? Edit the file on GitLab.

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