Libexpat Project: >> Libexpat >> 2.4.5 Security Vulnerabilities
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_ResumeParser from within handlers in cases of a policy violation. Thus, a use-after-free can occur (similar to the CVE-2026-50219 situation).
CVSS Score
4.9
EPSS Score
0.001
Published
2026-06-19
In libexpat before 2.8.2, there is a heap-based buffer overflow in doProlog in xmlparse.c because scaffold backing array reallocation is mishandled when there is data-structure sharing across parsers.
CVSS Score
6.9
EPSS Score
0.001
Published
2026-06-19
libexpat before 2.8.2 lacks handler call depth tracking for calls to XML_GetBuffer, XML_Parse, XML_ParseBuffer, XML_ParserFree, or XML_ParserReset from within handlers in cases of a policy violation. Thus, a use-after-free can occur,
CVSS Score
4.9
EPSS Score
0.002
Published
2026-06-04
In libexpat before 2.8.1, the computational complexity of attribute name collision checks allows a denial of service via moderately sized crafted XML input.
CVSS Score
2.9
EPSS Score
0.003
Published
2026-05-10
libexpat before 2.8.0 uses insufficient entropy, and thus hash flooding can occur via a crafted XML document.
CVSS Score
2.9
EPSS Score
0.004
Published
2026-04-16
libexpat before 2.7.5 allows a NULL pointer dereference with empty external parameter entity content.
CVSS Score
4.0
EPSS Score
0.001
Published
2026-03-16
libexpat before 2.7.5 allows an infinite loop while parsing DTD content.
CVSS Score
4.0
EPSS Score
0.002
Published
2026-03-16
libexpat before 2.7.5 allows a NULL pointer dereference in the function setContext on retry after an earlier ouf-of-memory condition.
CVSS Score
2.9
EPSS Score
0.001
Published
2026-03-16
In libexpat before 2.7.4, the doContent function does not properly determine the buffer size bufSize because there is no integer overflow check for tag buffer reallocation.
CVSS Score
6.9
EPSS Score
0.002
Published
2026-01-30
In libexpat before 2.7.4, XML_ExternalEntityParserCreate does not copy unknown encoding handler user data.
CVSS Score
2.9
EPSS Score
0.002
Published
2026-01-23