CVE-2023-6816Critical· 9.8▾ MidnightA flaw was found in X.Org server. Both DeviceFocusEvent and the XIQueryPointer reply contain a bit for each logical button currently down. Buttons can be arbitrarily mapped to any value up to 255, but the X.Org Server was only allocating…
▾ Midnight zone — Critical, or high with PoC / in-the-wild
impact 53.9 · likelihood 0.4 · exploitation 0
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Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.
Disclosure to exploitation, from the record and what we observed since indexing it.
Disclosed via CVEORG
Last analysed / modified upstream
2.1%
A flaw was found in X.Org server. Both DeviceFocusEvent and the XIQueryPointer reply contain a bit for each logical button currently down. Buttons can be arbitrarily mapped to any value up to 255, but the X.Org Server was only allocating space for the device's particular number of buttons, leading to a heap overflow if a bigger value was used.
tigervnc (all versions)xorg-x11-server (all versions)tigervnc (all versions)tigervnc (all versions)xorg-x11-server (all versions)xorg-x11-server-Xwayland (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)tigervnc (all versions)xorg-x11-server (all versions)xorg-x11-server-Xwayland (all versions)tigervnc (all versions)tigervnc (all versions)xorg-x11-serverRefer to the linked advisories for vendor-supplied fixes and affected version ranges.
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Connected by shared product, vendor, weakness, or advisory.
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