Denial of service via Schematron pointer reuse
Published Jun 16, 2025 · Updated Aug 16, 2026
Use-after-free in XML Schematron parsing in XMLSoft libxml2 before 2.15.0 allows attackers to crash applications with crafted XML. xmlSchematronGetNode returns a pointer to freed memory while processing an sch:name path expression, and later code dereferences it. Exploitation requires a consuming application to parse an attacker-controlled Schematron schema; the resulting undefined behavior can interrupt that process.
Summary
What happened
Use-after-free in XML Schematron parsing in XMLSoft libxml2 before 2.15.0 allows attackers to crash applications with crafted XML. xmlSchematronGetNode returns a pointer to freed memory while processing an sch:name path expression, and later code dereferences it. Exploitation requires a consuming application to parse an attacker-controlled Schematron schema; the resulting undefined behavior can interrupt that process.
The record
- CVE
- CVE-2025-49794
- Published
- Jun 16, 2025
- Updated
- Aug 16, 2026
- Vendor
- XMLSoft
- Product
- libxml2
- Classifications
- CWE-416, T1499.004
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 16, 2025CVE publishedPublication date reported by the CVE source.
- Aug 16, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=0 <2.15.0
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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