CVE-2026-102633
libexpat 2.7.2 through 2.8.5 Integer Overflow in expat_realloc
CVSS Score
5.9
EPSS Score
0.0%
EPSS Percentile
0th
libexpat versions 2.7.2 through 2.8.5 contain an integer overflow vulnerability in expat_realloc() function on 32-bit platforms when computing allocation sizes. Attackers supplying malicious XML to applications parsing with vulnerable libexpat can cause heap buffer overflow, memory corruption, or denial of service.
| CWE | CWE-190 |
| Vendor | libexpat |
| Product | libexpat |
| Published | Sep 29, 2026 |
| Last Updated | Sep 29, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Attack Vector
Network
Attack Complexity
High
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Affected Versions
libexpat / libexpat
2.7.2 ≤ 2.8.5
References
github.com: https://github.com/libexpat/libexpat/pull/1392 github.com: https://github.com/libexpat/libexpat/commit/209801d7fbaf07ab74bae8cb32dd2ab9e5846118 github.com: https://github.com/libexpat/libexpat/blob/R_2_8_5/expat/lib/xmlparse.c#L1003 github.com: https://github.com/libexpat/libexpat vulncheck.com: https://www.vulncheck.com/advisories/libexpat-2.7.2-through-2.8.5-integer-overflow-in-expat-realloc
Credits
Filippo Tedeschi Matthew Fernandez Filippo Tedeschi