CVE-2026-113351

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 v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/libexpat/libexpat
https://github.com/libexpat/libexpat/blob/a76b1174c1ea52abb639a4c69d52b630a8a106a2/expat/lib/xmlparse.c#L1560
https://github.com/libexpat/libexpat/blob/a76b1174c1ea52abb639a4c69d52b630a8a106a2/expat/lib/xmlparse.c#L860-L884
https://github.com/libexpat/libexpat/pull/1431
https://www.vulncheck.com/advisories/libexpat-2.7.2-through-2.9.0-denial-of-service-via-xml-parserreset

Configurations

No configuration.

History

20 Oct 2026, 11:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 11:17

Updated : 2026-10-20 20:06

NVD link : CVE-2026-113351

Mitre link : CVE-2026-113351

CVE.ORG link : CVE-2026-113351

JSON object : View

Products Affected

No product.

CWE

CWE-909

Missing Initialization of Resource

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