CVE-2026-26824
libxls: Use of Uninitialized Memory in OLE Container Parser
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
INFO
Published Date :
June 3, 2026, 8:16 p.m.
Last Modified :
June 4, 2026, 6:41 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 134c704f-9b21-4f2e-91b3-4a467353bcc0 |
Solution
- Update libxls to a patched version.
- Avoid processing untrusted XLS files.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-26824.
| URL | Resource |
|---|---|
| https://github.com/libxls/libxls/issues/155 | Exploit Issue Tracking |
| https://github.com/libxls/libxls/issues/155 | Exploit Issue Tracking |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-26824 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-26824
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-26824 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-26824 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 04, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:libxls_project:libxls:*:*:*:*:*:*:*:* versions up to (including) 1.6.3 Added Reference Type CISA-ADP: https://github.com/libxls/libxls/issues/155 Types: Exploit, Issue Tracking Added Reference Type MITRE: https://github.com/libxls/libxls/issues/155 Types: Exploit, Issue Tracking -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jun. 04, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:L Added CWE CWE-457 Added Reference https://github.com/libxls/libxls/issues/155 -
New CVE Received by [email protected]
Jun. 03, 2026
Action Type Old Value New Value Added 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 Added Reference https://github.com/libxls/libxls/issues/155