CVE-2026-26825

A use-of-uninitialized memory vulnerability exists in libxls 1.6.3 when parsing malformed XLS files. The issue is reachable via xls_parseWorkBook() and is triggered by uninitialized heap memory originating from the OLE layer (ole2_read). The flaw is detectable with MemorySanitizer (MSAN) and can lead to undefined behavior, incorrect parsing logic, or potential information disclosure.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/libxls/libxls/issues/156	Exploit Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:libxls_project:libxls:1.6.3:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-06-03 20:16

Updated : 2026-07-22 20:10

NVD link : CVE-2026-26825

Mitre link : CVE-2026-26825

CVE.ORG link : CVE-2026-26825

JSON object : View

Products Affected

libxls_project

libxls

CWE

CWE-908

Use of Uninitialized Resource

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