CVE-2026-50258 (GCVE-0-2026-50258)
Vulnerability from cvelistv5
Published
2026-06-05 10:31
Modified
2026-06-10 03:58
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-121 - Stack-based Buffer Overflow
Summary
A stack-based buffer overflow flaw was found in the X.Org X server and Xwayland. The X server has multiple stack buffers sized XkbMaxShiftLevel * XkbNumKbdGroups but CheckKeyTypes() does not verify or clamp non-canonical key types to XkbMaxShiftLevel. A client can change key types to excessive shift levels and trigger stack overflows. This is caused by an incomplete fix of CVE-2025-26597. This may be used to crash the server, or for privilege escalation if the X server runs as root.
References
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Impacted products
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|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Red Hat | Red Hat Enterprise Linux 10 |
cpe:/o:redhat:enterprise_linux:10 |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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