Expat: Denial of Service and Information Disclosure vulnerability
A vulnerability in the expat XML parsing library allows a remote, unauthenticated attacker to trigger a denial-of-service condition or potentially disclose sensitive information.
Triage facts
Revision 1- Applicability
- expat
- Evidence
- Unknown
- Severity
- Medium
- Action
- Elevated
- Sources
- 1 public source
- Freshness
- Revision 1Nov 9, 16:09 UTC
- Source quality
- B2Roughly even chance
The BSI has reported a vulnerability in the expat XML parsing library. A remote, unauthenticated attacker can exploit this flaw to cause a denial-of-service (DoS) or potentially disclose sensitive information. No CVE identifier or patch details are currently available in the source notice.
Recommendation
- Inventory internal applications and software stacks that utilize the libexpat library to identify exposure.
- Monitor vendor security channels for updates to the expat library and related software distributions.
- Implement application-level resource limiting and input validation for systems parsing XML data from untrusted sources.
Immediate actions
Perform an organization-wide inventory of software products and custom applications that link against libexpat.
Threat Hunt
Identify applications parsing untrusted XML content that may be susceptible to resource exhaustion attacks.
Data: Application logs, Web server error logs, System resource monitoring (CPU/Memory usage spikes during XML processing)
Mitigations
Apply security patches for expat once released by distributions or vendor maintainers.
expat library
Gaps
- Missing CVE and specific vulnerable version range; identification of impacted systems currently relies on generic software scanning.