Webrecorder pywb before 2.6.0 allows XSS because it does not ensure that Jinja2 templates are autoes...

pywb Updated 02 Oct 2025

Summary

18/08/2021

Disclosed on

CVE-2021-39286

CVE

Yes i

Fix available

Moderate

Severity

6.1

CVSS Score

CVE-2021-39286: Webrecorder pywb before 2.6.0 allows XSS because it does not ensure that Jinja2 templates are autoescaped. Affects pywb across 2 version ranges.

< 2.6.0 < f7bd84cdacdd665ff73ae8d09a202f60be2ebae9

Fixed in f7bd84cdacdd665ff73ae8d09a202f60be2ebae9. How to fix ↓

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Webrecorder pywb before 2.6.0 allows XSS because it does not ensure that Jinja2 templates are autoescaped.

How To Fix

Latest published version: 2.10.0 as of 22 Oct 2026

pip install --upgrade "pywb==2.10.0"

Upgrading to it may include breaking changes; the version below is the minimum fixed release for this vulnerability.

If you need the minimum change

f7bd84cdacdd665ff73ae8d09a202f60be2ebae9

This is the first release that contains the fix.

pip install --upgrade "pywb==f7bd84cdacdd665ff73ae8d09a202f60be2ebae9"

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References