CVE-2026-102633libexpat 2.7.2 through 2.8.5 Integer Overflow in expat_realloc
Updated under an hour ago ()
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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.
- CVSS
- 5.9 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weakness (CWE)
- CWE-190
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- VulnCheck
- NVD analysis
- Awaiting Analysis
- Record last updated
- Sep 29, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
libexpat libexpat libexpat:libexpat (from the name) | from 2.7.2 through 2.8.5 | CNA record |
References
- https://github.com/libexpat/libexpat/pull/1392issue-tracking, patch
- https://github.com/libexpat/libexpat/commit/209801d7fbaf07ab74bae8cb32dd2ab9e5846118patch
- https://github.com/libexpat/libexpat/blob/R_2_8_5/expat/lib/xmlparse.c#L1003technical-description
- https://github.com/libexpat/libexpatproduct
- https://www.vulncheck.com/advisories/libexpat-2.7.2-through-2.8.5-integer-overflow-in-expat-reallocthird-party-advisory
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.