CVSS 4.0
6.3 mediumCVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:L/SC:N/SI:N/SA:NCVE-2026-124317
Medium (6.3).
libexpat through 2.10.0 contains an out-of-bounds read vulnerability in unknown_toUtf8() and unknown_toUtf16() in xmltok.c when handling application-registered unknown encodings. Attackers can supply a document ending in a truncated multibyte sequence so the convert callback reads past the parse buffer, leaking adjacent memory or crashing applications.
Severity
CVSS 3.1
4.8 mediumCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:L- CWE
- CWE-126 Buffer Over-read
- Published
- Modified
- Record from
- the NVD, synced
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Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| libexpat | through 2.10.0 |
References
- https://github.com/libexpat/libexpat
- https://github.com/libexpat/libexpat/blob/a70841d9ffa64ddde29ab824ed6305035ebe4c47/expat/lib/xmltok.c#L1274-L1322
- https://github.com/libexpat/libexpat/pull/1492
- https://www.vulncheck.com/advisories/libexpat-through-2.10.0-out-of-bounds-read-via-unknown-toutf8-and-unknown-toutf16