REXML denial of service vulnerability

Impact

The REXML gem before 3.3.6 has a DoS vulnerability when it parses an
XML that has many deep elements that have same local name attributes.

If you need to parse untrusted XMLs with tree parser API like
REXML::Document.new, you may be impacted to this vulnerability.
If you use other parser APIs such as stream parser API and SAX2
parser API, this vulnerability is not affected.

This vulnerability has been assigned the CVE identifier CVE-2024-43398.
We strongly recommend upgrading the REXML gem.

Patches

The REXML gem 3.3.6 or later include the patch to fix the
vulnerability.

Workarounds

Don’t parse untrusted XMLs with tree parser API.

Affected versions

REXML gem 3.3.5 or prior

Credits

Thanks to l33thaxor for discovering this issue.

History

Originally published at 2024-08-22 03:00:00 (UTC)