Stack-Based Buffer Overflow in X.Org X Server and Xwayland
CVE-2026-50259
Key Information:
- Vendor
Red Hat
- Status
- Vendor
- CVE Published:
- 5 June 2026
What is CVE-2026-50259?
A stack-based buffer overflow vulnerability was discovered in the X.Org X server and Xwayland, specifically in the _XkbSetMapChecks() function. This function utilizes a fixed-size stack buffer, mapWidths[256], which is indexed by key type index. The CheckKeyTypes() helper function can write to this buffer using a client-controlled offset, which causes a stack buffer overflow. Exploiting this vulnerability could lead to server crashes or, if the X server operates with root privileges, potential privilege escalation.
Affected Version(s)
Red Hat Enterprise Linux 10 0:24.1.9-4.el10_2.2
Red Hat Enterprise Linux 10.0 Extended Update Support 0:24.1.5-6.el10_0.1
Red Hat Enterprise Linux 7 Extended Lifecycle Support 0:1.20.4-35.el7_9
References
CVSS V3.1
Timeline
Vulnerability published
Vulnerability Reserved