libxls up to 1.6.3 OLE Container Parser read_MSAT uninitialized pointer

CVSS Meta Temp Score
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CTI Interest Score
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5.5$0-$5k1.50-

Summaryinfo

A vulnerability categorized as critical has been discovered in libxls up to 1.6.3. This affects the function read_MSAT of the component OLE Container Parser. Such manipulation leads to uninitialized pointer. This vulnerability is uniquely identified as CVE-2026-26824. No exploit exists.

Detailsinfo

A vulnerability was found in libxls up to 1.6.3 and classified as critical. Affected by this issue is the function read_MSAT of the component OLE Container Parser. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. Using CWE to declare the problem leads to CWE-824. The product accesses or uses a pointer that has not been initialized. The impact remains unknown. CVE summarizes:

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

The advisory is available at github.com. This vulnerability is handled as CVE-2026-26824 since 02/16/2026. The exploitation is known to be easy. Technical details are known, but there is no available exploit.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

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Productinfo

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.5
VulDB Meta Temp Score: 5.5

VulDB Base Score: 5.5
VulDB Temp Score: 5.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Uninitialized pointer
CWE: CWE-824 / CWE-908
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Partially

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

02/16/2026 CVE reserved
06/03/2026 +106 days Advisory disclosed
06/03/2026 +0 days VulDB entry created
06/03/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 155
Status: Confirmed

CVE: CVE-2026-26824 (🔒)
GCVE (CVE): GCVE-0-2026-26824
GCVE (VulDB): GCVE-100-368222

Entryinfo

Created: 06/03/2026 22:40
Changes: 06/03/2026 22:40 (53)
Complete: 🔍
Cache ID: 216::103

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