CVE-2026-56000
Last modified
CVE-2026-56000 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.. EPSS estimates a 0.21% chance of exploitation in the next 30 days.
Description
Local attackers with a X connection able to provide GLX commit to the X server xorg-server before 21.2.24 and xwayland before 24.1.13 could cause a Heap Use After Free, due to CommonMakeCurrent() pointing into potentially reallocated memory.
Metrics
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| X.Org | X Server | < 21.2.24 |
| X.Org | Xwayland | < 24.1.13 |
References
- https://www.openwall.com/lists/oss-security/2026/07/08/2Mailing List, Patch, Third Party Advisory
Timeline
- Published
- Last Modified
- Status
- Analyzed
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