Description
build_model in xmlparse.c in Expat (aka libexpat) before 2.4.3 has an integer overflow.
Affected products
libexpat_project: libexpat; tenable: nessus; debian: debian linux; siemens: sinema remote connect server
References10
- cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf PatchThird Party Advisory
- cert-portal.siemens.com/productcert/pdf/ssa-484086.pdf PatchThird Party Advisory
- www.openwall.com/lists/oss-security/2022/01/17/3 Mailing ListThird Party Advisory
- github.com/libexpat/libexpat/pull/539 Third Party Advisory
- security.gentoo.org/glsa/202209-24 Third Party Advisory
- www.debian.org/security/2022/dsa-5073 Third Party Advisory
- www.tenable.com/security/tns-2022-05 Third Party Advisory
- www.openwall.com/lists/oss-security/2022/01/17/3 Mailing ListThird Party Advisory
- github.com/libexpat/libexpat/pull/539 Third Party Advisory
- security.gentoo.org/glsa/202209-24 Third Party Advisory
Metrics
- CVSS 3.1
-
9.8
CRITICAL
Score source: NVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - EPSS — exploit probability
- 4% percentile: 90 · as of 4 November 2026
- CWE
- CWE-190
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