Privilege escalation via recursive device disablement
Published Feb 28, 2024 · Updated Nov 6, 2025
Heap buffer overflow in X.Org Server and Xwayland allows local users to escalate privileges by disabling nested input devices. DisableDevice recursively moves a master and its disabled slaves between linked lists while retaining a stale prev pointer, corrupting device-count accounting and underallocating a later array. The flaw can crash the X server or execute code, including through an authenticated SSH X11-forwarding session.
Summary
What happened
Heap buffer overflow in X.Org Server and Xwayland allows local users to escalate privileges by disabling nested input devices. DisableDevice recursively moves a master and its disabled slaves between linked lists while retaining a stale prev pointer, corrupting device-count accounting and underallocating a later array. The flaw can crash the X server or execute code, including through an authenticated SSH X11-forwarding session.
The record
- CVE
- CVE-2024-21886
- Published
- Feb 28, 2024
- Updated
- Nov 6, 2025
- Vendor
- Red Hat
- Product
- Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support
- Classifications
- CWE-122, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Feb 28, 2024CVE publishedPublication date reported by the CVE source.
- Nov 6, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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