Application crash via dangling namespace pointers
Published Mar 14, 2025 · Updated Nov 3, 2025
Use-after-free in XMLSoft libxslt before 1.1.43 allows attackers to crash or corrupt applications via crafted XSLT stylesheets. The parser stores excluded-namespace URI pointers in exclPrefixTab, but xsltParseTemplateContent can delete the defining nodes before xsltGetInheritedNsList dereferences those pointers. Exploitation requires processing a stylesheet with an included xsl:text root and excluded result prefix; public proof demonstrates an AddressSanitizer-detected heap read, not code execution.
Summary
What happened
Use-after-free in XMLSoft libxslt before 1.1.43 allows attackers to crash or corrupt applications via crafted XSLT stylesheets. The parser stores excluded-namespace URI pointers in exclPrefixTab, but xsltParseTemplateContent can delete the defining nodes before xsltGetInheritedNsList dereferences those pointers. Exploitation requires processing a stylesheet with an included xsl:text root and excluded result prefix; public proof demonstrates an AddressSanitizer-detected heap read, not code execution.
The record
- CVE
- CVE-2024-55549
- Published
- Mar 14, 2025
- Updated
- Nov 3, 2025
- Vendor
- XMLSoft
- Product
- libxslt
- Classifications
- CWE-416
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Mar 14, 2025CVE publishedPublication date reported by the CVE source.
- Nov 3, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
Compare your product and version with the public record. A matching version still requires validation against your environment.
Is a vulnerable build present?
Compare these published version ranges with your installed build and any vendor patches.
- Affected versionversion=0 <1.1.43
What conditions does exploitation require?
What is affected?
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Weakness, pattern, technique
Public exploit references
- libxslt xsltParseStylesheetProcess use-after-free reproducerproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Technologies
Your stack
See the directory against your own environment.
Your stack
Check the software in your environment
Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.
Book a demo