REXML has a DoS condition when parsing malformed XML file
REXML is an XML toolkit for Ruby. The REXML gems from 3.3.3 to 3.4.1 has a DoS vulnerability when parsing XML containing multiple XML declarations. If you need to parse untrusted XMLs, you may be impacted to these vulnerabilities. The REXML gem 3.4.2 or later include the patches to fix these vulnerabilities.
02 / AFFECTED SOFTWARE
Affected packages
9 explicit affected versions
9 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
REXML is an XML toolkit for Ruby. The REXML gems from 3.3.3 to 3.4.1 has a DoS vulnerability when parsing XML containing multiple XML declarations. If you need to parse untrusted XMLs, you may be impacted to these vulnerabilities. The REXML gem 3.4.2 or later include the patches to fix these vulnerabilities.
### Impact The REXML gems from 3.3.3 to 3.4.1 have a DoS vulnerability when parsing XML containing multiple XML declarations. If you need to parse untrusted XMLs, you may be impacted to these vulnerabilities. ### Patches REXML gems 3.4.2 or later include the patches to fix these vulnerabilities. ### Workarounds Don't parse untrusted XMLs. ### References * https://www.ruby-lang.org/en/news/2025/09/18/dos-rexml-cve-2025-58767/ : An announcement on www.ruby-lang.org
05 / REFERENCES
Further evidence
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/58xxx/CVE-2025-58767.json
- https://github.com/ruby/rexml/commit/5859bdeac792687eaf93d8e8f0b7e3c1e2ed5c23
- https://github.com/ruby/rexml/security/advisories/GHSA-c2f4-jgmc-q2r5
- https://nvd.nist.gov/vuln/detail/CVE-2025-58767
- https://github.com/ruby/rexml
- https://github.com/rubysec/ruby-advisory-db/blob/master/gems/rexml/CVE-2025-58767.yml
- https://www.ruby-lang.org/en/news/2025/09/18/dos-rexml-cve-2025-58767