CVE-2026-26825
Medium
Description
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.
SeverityMedium
CVSS5.3
Exploit probability—
ProductLibxls
PublishedJun 3, 2026
First seenJun 3, 2026
Weakness typeCWE-908CWE-908
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| libxls_project libxls | 1.6.3 | — |
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