Medium severity · published Oct 20, 2026
CVE-2026-113351
libexpat 2.7.2 through 2.9.0 Denial of Service via XML_ParserReset
5.9
CVSS
0.5%
EPSS
No
On KEV
Description
libexpat 2.7.2 through 2.9.0 contains a denial of service vulnerability because XML_ParserReset zeroes the direct byte count but never offsets tracked heap allocations. Attackers can submit a large XML document so later documents on the same reset parser fail with XML_ERROR_NO_MEMORY until it is recreated.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
LI
libexpat · libexpat
2.7.2 through 2.9.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-113351
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-113351
github.com
https://github.com/libexpat/libexpat
github.com
https://github.com/libexpat/libexpat/blob/a76b1174c1ea52abb639a4c69d52b630a8a106a2/expat/lib/xmlparse.c#L1560
github.com
https://github.com/libexpat/libexpat/blob/a76b1174c1ea52abb639a4c69d52b630a8a106a2/expat/lib/xmlparse.c#L860-L884
github.com
https://github.com/libexpat/libexpat/pull/1431
www.vulncheck.com
https://www.vulncheck.com/advisories/libexpat-2.7.2-through-2.9.0-denial-of-service-via-xml-parserreset
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