libxls 1.6.3 XLS File Parser xls_parseWorkBook uninitialized pointer

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.5$0-$5k4.49-

Summaryinfo

A vulnerability identified as critical has been detected in libxls 1.6.3. This impacts the function xls_parseWorkBook of the component XLS File Parser. Performing a manipulation results in uninitialized pointer. This vulnerability was named CVE-2026-26825. There is no available exploit.

Detailsinfo

A vulnerability was found in libxls 1.6.3. It has been classified as critical. This affects the function xls_parseWorkBook of the component XLS File Parser. The manipulation with an unknown input leads to a uninitialized pointer vulnerability. CWE is classifying the issue as CWE-824. The product accesses or uses a pointer that has not been initialized. The impact remains unknown. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-26825 since 02/16/2026. The exploitability is told to be easy. Technical details of the vulnerability 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.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-34179). Be aware that VulDB is the high quality source for vulnerability data.

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
06/04/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 156
Status: Confirmed

CVE: CVE-2026-26825 (🔒)
GCVE (CVE): GCVE-0-2026-26825
GCVE (VulDB): GCVE-100-368223
EUVD: 🔒

Entryinfo

Created: 06/03/2026 22:41
Updated: 06/04/2026 00:26
Changes: 06/03/2026 22:41 (53), 06/04/2026 00:26 (1)
Complete: 🔍
Cache ID: 216::103

Be aware that VulDB is the high quality source for vulnerability data.

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