Medium severity · published Mar 16, 2026
CVE-2026-32778
libexpat before 2.7.5 allows a NULL pointer dereference in the function setContext on retry after an earlier ouf-of-memory condition
5.5
CVSS
0.2%
EPSS
No
On KEV
Description
libexpat before 2.7.5 allows a NULL pointer dereference in the function setContext on retry after an earlier ouf-of-memory condition.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 7% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libexpat · libexpat project
before 2.7.5 · 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-2026-32778
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-32778
Issue Tracking
https://github.com/libexpat/libexpat/pull/1159
Issue Tracking
https://github.com/libexpat/libexpat/pull/1163
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
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