Bug 1916614 (CVE-2021-21236) - CVE-2021-21236 cairosvg: regex vulnerable to a REDoS
Summary: CVE-2021-21236 cairosvg: regex vulnerable to a REDoS
Alias: CVE-2021-21236
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
Depends On: 1916615 1916616
TreeView+ depends on / blocked
Reported: 2021-01-15 09:36 UTC by Marian Rehak
Modified: 2021-01-15 12:27 UTC (History)
2 users (show)

Fixed In Version:
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Last Closed: 2021-01-15 12:27:45 UTC

Attachments (Terms of Use)

Description Marian Rehak 2021-01-15 09:36:59 UTC
CairoSVG is a Python (pypi) package. CairoSVG is an SVG converter based on Cairo. In CairoSVG before version 2.5.1, there is a regular expression denial of service (REDoS) vulnerability. When processing SVG files, the python package CairoSVG uses two regular expressions which are vulnerable to Regular Expression Denial of Service (REDoS). If an attacker provides a malicious SVG, it can make cairosvg get stuck processing the file for a very long time. This is fixed in version 2.5.1. See Referenced GitHub advisory for more information.


Comment 1 Marian Rehak 2021-01-15 09:37:29 UTC
Created python-cairosvg tracking bugs for this issue:

Affects: epel-7 [bug 1916616]
Affects: fedora-all [bug 1916615]

Comment 2 Felix Schwarz 2021-01-15 10:50:20 UTC
This is already fixed for Fedora since 2021-01-07. Updated cairosvg versions were pushed to stable tonight:
- https://bodhi.fedoraproject.org/updates/FEDORA-2021-8537865fb5
- https://bodhi.fedoraproject.org/updates/FEDORA-2021-a2d05a2e65

The Fedora updates above contain a "backported" patch which was approved upstream: https://github.com/Kozea/CairoSVG/issues/308#issuecomment-755780444

Comment 3 Felix Schwarz 2021-01-15 10:50:55 UTC
sorry, I meant to add comment 2 into the box for bug 1916615, reopening.

Comment 4 Product Security DevOps Team 2021-01-15 12:27:45 UTC
This CVE Bugzilla entry is for community support informational purposes only as it does not affect a package in a commercially supported Red Hat product. Refer to the dependent bugs for status of those individual community products.

Note You need to log in before you can comment on or make changes to this bug.