CVE-2024-21886: Heap-based Buffer Overflow
Source CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 1.4% chance of exploitation in 30 days – higher than 72% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 28 Feb 2024
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-25.
What to do
AI-suggested
Organizations should immediately verify if they are running the affected X.Org server version 1.21.1.7 and plan to apply vendor patches as soon as they are released. Until patches are available, disabling SSH X11 forwarding can significantly reduce the attack surface by preventing remote exploitation via this vector. Implement strict access controls to limit local user privileges and restrict who can initiate graphical sessions. Employ runtime protections such as heap memory protection mechanisms (e.g., ASLR, heap canaries) to mitigate exploitation attempts. Monitor system logs and network traffic for unusual activity related to X.Org or SSH sessions. Conduct regular vulnerability scanning and penetration testing focused on graphical server components. Educate system administrators about the risks of enabling X11 forwarding and encourage the use of alternative secure remote access methods when possible. Maintain up-to-date backups and incident response plans to quickly recover from potential compromises.
Description
A heap buffer overflow flaw was found in the DisableDevice function in the X.Org server. This issue may lead to an application crash or, in some circumstances, remote code execution in SSH X11 forwarding environments.
References
- access.redhat.com/errata/RHSA-2024:0320 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0557 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0558 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0597 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0607 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0614 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0617 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0621 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0626 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0629 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:2169 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:2170 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:2995 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:2996 (opens in a new tab)
- access.redhat.com/errata/RHSA-2025:12751 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2024-21886 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2256542 (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IZ75X54CN4IFYMIV7OK3JVZ57FHQIGIC/ (opens in a new tab)
- lists.debian.org/debian-lts-announce/2024/01/msg00016.html (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/EJBMCWQ54R6ZL3MYU2D2JBW6JMZL7BQW/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/5J4H7CH565ALSZZYKOJFYDA5KFLG6NUK/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TZ2IJJDHJETNE76VUX4G7UI5EG5HYFEH/ (opens in a new tab)