CVE-2026-26824: n/a
libxls through version 1.6.3 contains a use of uninitialized memory vulnerability in the OLE container parser. Memory allocated for the Master Sector Allocation Table (MSAT) in read_MSAT() is not fully initialized before being consumed by ole2_validate_sector_chain(), which may result in application crashes or potential information disclosure when processing a crafted XLS file
AI Analysis
Technical Summary
CVE-2026-26824 describes a use of uninitialized memory vulnerability in libxls through version 1.6.3. The issue arises because the memory allocated for the Master Sector Allocation Table (MSAT) in the read_MSAT() function is not completely initialized before consumption by ole2_validate_sector_chain(). This can cause the application to crash or potentially leak information when handling crafted XLS files. The vulnerability is classified under CWE-457 (Use of Uninitialized Variable). No official patch or remediation level has been provided as of the published date.
Potential Impact
Exploitation of this vulnerability may cause application crashes (availability impact) or potential information disclosure (confidentiality impact) when processing malicious XLS files. There are no known exploits in the wild. The vulnerability does not require privileges or user interaction to be triggered and can be exploited remotely over the network.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or patch is currently available, users should exercise caution when processing untrusted XLS files with libxls versions up to 1.6.3. Monitoring vendor channels for updates is recommended.
CVE-2026-26824: n/a
Description
libxls through version 1.6.3 contains a use of uninitialized memory vulnerability in the OLE container parser. Memory allocated for the Master Sector Allocation Table (MSAT) in read_MSAT() is not fully initialized before being consumed by ole2_validate_sector_chain(), which may result in application crashes or potential information disclosure when processing a crafted XLS file
CVSS v3.1
Score 6.5medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-26824 describes a use of uninitialized memory vulnerability in libxls through version 1.6.3. The issue arises because the memory allocated for the Master Sector Allocation Table (MSAT) in the read_MSAT() function is not completely initialized before consumption by ole2_validate_sector_chain(). This can cause the application to crash or potentially leak information when handling crafted XLS files. The vulnerability is classified under CWE-457 (Use of Uninitialized Variable). No official patch or remediation level has been provided as of the published date.
Potential Impact
Exploitation of this vulnerability may cause application crashes (availability impact) or potential information disclosure (confidentiality impact) when processing malicious XLS files. There are no known exploits in the wild. The vulnerability does not require privileges or user interaction to be triggered and can be exploited remotely over the network.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or patch is currently available, users should exercise caution when processing untrusted XLS files with libxls versions up to 1.6.3. Monitoring vendor channels for updates is recommended.
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: 6a208c1fe29bf47b50e773ec
Added to database: 06/03/2026, 20:18:39 UTC
Last enriched: 06/10/2026, 21:00:22 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 81
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