CVE-2023-6816Xorg-x11-server: heap buffer overflow in devicefocusevent and procxiquerypointer

Description

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.

Timeline

Scores

EPSS (exploitation in 30 days)

2.1% · top 18% of all CVEs (14 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Critical 9.8.

Affected products

• Red Hat · Red Hat Enterprise Linux 6 Extended Lifecycle Support - EXTENSION

  • unaffected 0:1.1.0-25.el6_10.13 – < *

• Red Hat · Red Hat Enterprise Linux 7

  • unaffected 0:1.20.4-27.el7_9 – < *

• Red Hat · Red Hat Enterprise Linux 7

  • unaffected 0:1.8.0-31.el7_9 – < *

• Red Hat · Red Hat Enterprise Linux 8

  • unaffected 0:1.13.1-2.el8_9.7 – < *

• Red Hat · Red Hat Enterprise Linux 8

  • unaffected 0:1.20.11-22.el8 – < *

• Red Hat · Red Hat Enterprise Linux 8

  • unaffected 0:21.1.3-15.el8 – < *

• Red Hat · Red Hat Enterprise Linux 8.2 Advanced Update Support

  • unaffected 0:1.9.0-15.el8_2.9 – < *

• Red Hat · Red Hat Enterprise Linux 8.2 Telecommunications Update Service

  • unaffected 0:1.9.0-15.el8_2.9 – < *

• Red Hat · Red Hat Enterprise Linux 8.2 Update Services for SAP Solutions

  • unaffected 0:1.9.0-15.el8_2.9 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

  • unaffected 0:1.11.0-8.el8_4.8 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Telecommunications Update Service

  • unaffected 0:1.11.0-8.el8_4.8 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions

  • unaffected 0:1.11.0-8.el8_4.8 – < *

• Red Hat · Red Hat Enterprise Linux 8.6 Extended Update Support

  • unaffected 0:1.12.0-6.el8_6.9 – < *

• Red Hat · Red Hat Enterprise Linux 8.8 Extended Update Support

  • unaffected 0:1.12.0-15.el8_8.7 – < *

• Red Hat · Red Hat Enterprise Linux 9

  • unaffected 0:1.13.1-3.el9_3.6 – < *

• Red Hat · Red Hat Enterprise Linux 9

  • unaffected 0:1.20.11-24.el9 – < *

• Red Hat · Red Hat Enterprise Linux 9

  • unaffected 0:22.1.9-5.el9 – < *

• Red Hat · Red Hat Enterprise Linux 9.0 Extended Update Support

  • unaffected 0:1.11.0-22.el9_0.8 – < *

• Red Hat · Red Hat Enterprise Linux 9.2 Extended Update Support

  • unaffected 0:1.12.0-14.el9_2.5 – < *

• Red Hat · Red Hat Enterprise Linux 6

  All versions: unknown

What to do

Workaround: 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.

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2023-59026 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2023-6816](https://cveledger.app/badge/CVE-2023-6816.svg)](https://cveledger.app/cve/CVE-2023-6816)

Record last updated 4 Nov 2026, 21:07 UTC.