REXML denial of service vulnerability

Answer in brief

CVE-2024-39908 records a Medium severity (CVSS 4.3) vulnerability in REXML denial of service vulnerability. The current sources do not mark it as known exploited. The current feed maps rexml (rubygems). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jul 16, 2024Updated Sep 10, 2026Source checked Sep 10, 2026First seen by HOL Aug 7, 2026Material review Sep 10, 2026

Upstream Advisory

Key facts

Risk: Medium · CVSS 4.3
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

CVSS is 4.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps rexml (rubygems). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
rexmlrubygems	>=0 <3.3.2	3.3.2

Recommended response

Check inventory. Check lockfiles and deployed manifests for rexml.
Review the reported fix. Update rexml to 3.3.2 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 16, 2024
Evidence: source:osv:source_dates:source-dates:record
Source modified
Sep 10, 2026
Evidence: source:osv:source_dates:source-dates:record
First seen by HOL
Aug 7, 2026

Sources and claim methodology

Upstream source description

### Impact The REXML gem before 3.3.1 has some DoS vulnerabilities when it parses an XML that has many specific characters such as `<`, `0` and `%>`. If you need to parse untrusted XMLs, you may be impacted to these vulnerabilities. ### Patches The REXML gem 3.3.2 or later include the patches to fix these vulnerabilities. ### Workarounds Don't parse untrusted XMLs. ### References * https://github.com/ruby/rexml/security/advisories/GHSA-vg3r-rm7w-2xgh : This is a similar vulnerability * https://www.ruby-lang.org/en/news/2024/07/16/dos-rexml-cve-2024-39908/

Quoted source text, attributed separately from HOL analysis.