Medium severity · published Aug 10, 2026
CVE-2026-72522
libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same as high surrogates during Unicode processing in the…
6.2
CVSS
0.2%
EPSS
No
On KEV
Description
libexpat before 2.8.3 has an out-of-bounds read and resultant infinite loop because low surrogates are treated the same as high surrogates during Unicode processing in the *_toUtf16 functions.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.2% · higher than 9% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libexpat · libexpat project
before 2.8.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-72522
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-72522
bugzilla.mozilla.org
https://bugzilla.mozilla.org/show_bug.cgi?id=2053153
github.com
https://github.com/libexpat/libexpat/pull/1296
www.openwall.com
http://www.openwall.com/lists/oss-security/2026/08/11/5
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