CVE-2025-26598: tigervnc Memory Corruption (CVSS 7.8)

Description

An out-of-bounds write flaw was found in X.Org and Xwayland. The function GetBarrierDevice() searches for the pointer device based on its device ID and returns the matching value, or supposedly NULL, if no match was found. However, the code will return the last element of the list if no matching device ID is found, which can lead to out-of-bounds memory access.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-787 Out-of-bounds Write

Affected Products

Vendor	Product	Versions
tigervnc	tigervnc	All
x.org	x_server	< 21.1.16
x.org	xwayland	< 24.1.6
redhat	enterprise_linux	All
redhat	enterprise_linux	All
redhat	enterprise_linux	All

References

Other References

https://access.redhat.com/errata/RHSA-2025:2500 https://access.redhat.com/errata/RHSA-2025:2502 https://access.redhat.com/errata/RHSA-2025:2861 https://access.redhat.com/errata/RHSA-2025:2862 https://access.redhat.com/errata/RHSA-2025:2865 https://access.redhat.com/errata/RHSA-2025:2866 https://access.redhat.com/errata/RHSA-2025:2873 https://access.redhat.com/errata/RHSA-2025:2874 https://access.redhat.com/errata/RHSA-2025:2875 https://access.redhat.com/errata/RHSA-2025:2879

Frequently Asked Questions

What is CVE-2025-26598? +

An out-of-bounds write flaw was found in X.Org and Xwayland. The function GetBarrierDevice() searches for the pointer device based on its device ID and returns the matching value, or supposedly NULL, if no match was found. However, the code will return the last element of the list if no matching device ID is found, which can lead to out-of-bounds memory access. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2025-26598? +

CVE-2025-26598 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2025-26598? +

CVE-2025-26598 affects products from redhat, tigervnc, x.org, specifically: enterprise_linux, tigervnc, x_server, xwayland. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2025-26598? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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