CVE-2026-117610

libexpat through 2.9.0 contains a NULL pointer dereference vulnerability in externalEntityInitProcessor2() in lib/xmlparse.c that mishandles the XML_TOK_NONE token from empty input. Attackers who control stream chunking can force an empty non-final first parse on an external entity subparser, causing a later parse to crash the application.

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#L3468-L3510
https://github.com/libexpat/libexpat/commit/7b0d50e4b1d16fafd55876260701e04279a7489d
https://github.com/libexpat/libexpat/pull/1444
https://www.vulncheck.com/advisories/libexpat-through-2.9.0-null-pointer-dereference-via-external-entity-subparser

Configurations

No configuration.

History

28 Oct 2026, 03:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-28 03:17

Updated : 2026-10-28 15:21

NVD link : CVE-2026-117610

Mitre link : CVE-2026-117610

CVE.ORG link : CVE-2026-117610

JSON object : View

Products Affected

No product.

CWE

CWE-476

NULL Pointer Dereference

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