Low severity · published Apr 16, 2026
CVE-2026-41080
libexpat before 2.8.0 uses insufficient entropy, and thus hash flooding can occur via a crafted XML document
2.9
CVSS
0.4%
EPSS
No
On KEV
Description
libexpat before 2.8.0 uses insufficient entropy, and thus hash flooding can occur via a crafted XML document.
CVSS vector
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Local
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 34% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libexpat · libexpat project
before 2.8.0 · source: vendor, NVD
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.5 before V3.1.6; V3.1.5 before V3.1.6 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.5 before V3.1.6; V3.1.5 before V3.1.6 · source: CISA
SS
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.5 before V3.1.6 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-41080
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-41080
Release Notes
https://blog.hartwork.org/posts/expat-2-8-0-released/
Issue Tracking
https://github.com/libexpat/libexpat/issues/47
Issue Tracking
https://github.com/libexpat/libexpat/pull/1183
Mailing List
https://www.openwall.com/lists/oss-security/2026/04/26/1
Mailing List
http://www.openwall.com/lists/oss-security/2026/04/26/1
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
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