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HIGH · 7.8

CVE-2025-26595

A buffer overflow flaw was found in X.Org and Xwayland. The code in XkbVModMaskText() allocates a fixed-sized buffer on the stack and copies the names of the virtual modifiers to that buffer. The code...

Vulnerability Description

A buffer overflow flaw was found in X.Org and Xwayland. The code in XkbVModMaskText() allocates a fixed-sized buffer on the stack and copies the names of the virtual modifiers to that buffer. The code fails to check the bounds of the buffer and would copy the data regardless of the size.

CVSS Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack Vector
LOCAL
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
HIGH

Affected Products

VendorProductVersions
TigervncTigervnc-
X.OrgX Server< 21.1.16
X.OrgXwayland< 24.1.6
RedhatEnterprise Linux7.0

Related Weaknesses (CWE)

CWE-121CWE-787

References

FAQ

What is CVE-2025-26595?

CVE-2025-26595 is a vulnerability with a CVSS score of 7.8 (HIGH). A buffer overflow flaw was found in X.Org and Xwayland. The code in XkbVModMaskText() allocates a fixed-sized buffer on the stack and copies the names of the virtual modifiers to that buffer. The code...

How severe is CVE-2025-26595?

CVE-2025-26595 has been rated HIGH with a CVSS base score of 7.8/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2025-26595?

Check the references section above for vendor advisories and patch information. Affected products include: Tigervnc Tigervnc, X.Org X Server, X.Org Xwayland, Redhat Enterprise Linux.