CVE-2026-26825: n/a
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.
AI Analysis
Technical Summary
This vulnerability in libxls 1.6.3 involves use of uninitialized memory triggered during the parsing of malformed XLS files. The issue is reachable through the xls_parseWorkBook() function and originates from uninitialized heap memory in the OLE layer (ole2_read). Detected by MemorySanitizer, the flaw can lead to undefined behavior, incorrect parsing logic, or potential information disclosure. There is no vendor advisory or patch available at this time.
Potential Impact
The vulnerability may result in undefined behavior or incorrect parsing of XLS files, which could lead to potential information disclosure. There is no indication of privilege escalation, denial of service, or code execution. The CVSS score of 5.3 reflects a medium impact primarily due to potential confidentiality loss.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should exercise caution when processing untrusted XLS files with libxls 1.6.3.
CVE-2026-26825: n/a
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.
CVSS v3.1
Score 5.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability in libxls 1.6.3 involves use of uninitialized memory triggered during the parsing of malformed XLS files. The issue is reachable through the xls_parseWorkBook() function and originates from uninitialized heap memory in the OLE layer (ole2_read). Detected by MemorySanitizer, the flaw can lead to undefined behavior, incorrect parsing logic, or potential information disclosure. There is no vendor advisory or patch available at this time.
Potential Impact
The vulnerability may result in undefined behavior or incorrect parsing of XLS files, which could lead to potential information disclosure. There is no indication of privilege escalation, denial of service, or code execution. The CVSS score of 5.3 reflects a medium impact primarily due to potential confidentiality loss.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, users should exercise caution when processing untrusted XLS files with libxls 1.6.3.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-02-16T00:00:00.000Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a208c1fe29bf47b50e773ef
Added to database: 06/03/2026, 20:18:39 UTC
Last enriched: 06/10/2026, 20:35:02 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 62
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