Junglewise Threat Intelligence

CVE-2025-10990: Ruby REXML ReDoS in hex numeric character references

CVE-2025-10990 · Severity: high · CVSS 7.5 · Published 2026-02-27

Vendors: Ruby, Red Hat.

Executive brief

REXML is a popular Ruby library used for parsing XML data. A flaw in how it handles specific character references allows a remote attacker to crash the application or cause it to become unresponsive by sending a specially crafted XML document. This results in a denial-of-service (DoS) condition, potentially disrupting business operations and service availability for applications relying on this library, including Red Hat Satellite.

Technical details

A flaw was found in the REXML library's handling of hex numeric character references (&#x...;) within XML documents. The vulnerability is classified as a Regular Expression Denial of Service (ReDoS) caused by inefficient regular expression complexity (CWE-1333). A remote, unauthenticated attacker can exploit this by providing a crafted XML document that triggers catastrophic backtracking during regex parsing, leading to excessive CPU consumption and service unavailability. This issue represents an incomplete fix for a previous vulnerability (CVE-2024-49761). Patches have been released by the Ruby REXML maintainers and downstream vendors like Red Hat.

Affected products

  • Ruby REXML Before 3.3.9
  • Red Hat Satellite 6.16, 6.17
  • Puppet puppet-agent 8.8.1-3.el8sat, 8.8.1-3.el9sat

Timeline

  • 2024-10-28: other: Original vulnerability CVE-2024-49761 disclosed
  • 2025-10-08: advisory: Red Hat published security advisory RHSA-2025:17606
  • 2026-02-27: disclosed: NVD published CVE-2025-10990 record

References