Medium severity · published Nov 28, 2025
CVE-2025-66382
In libexpat through 2.7.3, a crafted file with an approximate size of 2 MiB can lead to dozens of seconds of processing time
5.5
CVSS
0.2%
EPSS
No
On KEV
Description
In libexpat through 2.7.3, a crafted file with an approximate size of 2 MiB can lead to dozens of seconds of processing time.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 10% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libexpat · libexpat project
through 2.7.5 · source: vendor, NVD
RR
RUGGEDCOM RST2428P · Siemens
before V4.0 · source: CISA
SS
SIMATIC S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.5; V3.1.5 · source: CISA
SS
SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP · Siemens
V3.1.5; V3.1.5 · source: CISA
SS
SIPLUS S7-1500 CPU 1518-4 PN/DP MFP · Siemens
V3.1.5 · source: CISA
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-66382
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-66382
Issue Tracking
https://github.com/libexpat/libexpat/issues/1076
Mailing List
http://www.openwall.com/lists/oss-security/2025/12/02/1
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-082556.html
cert-portal.siemens.com
https://cert-portal.siemens.com/productcert/html/ssa-253495.html
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