CVE-2023-5367: Red Hat Enterprise Linux 6 Extended Lifecycle Support – EXTENSION · Out-of-bounds Write
Affects Red Hat Enterprise Linux 6 Extended Lifecycle Support – EXTENSIONSource CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 26 Oct 2026, 12:54 UTC
- EPSS
- 0.6% chance of exploitation in 30 days – higher than 48% 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 25 Oct 2023
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 26 Oct 2026.
What to do
AI-suggested
- Apply official patches from Red Hat as soon as they become available through Extended Lifecycle Support channels.
- Restrict local access to systems running RHEL 6 Extended Lifecycle Support, limiting user accounts and enforcing strict access controls.
- Monitor logs and system behavior for unusual activity related to X server property changes or crashes.
- Consider isolating legacy systems from critical network segments to reduce risk of lateral movement.
- Where patching is delayed, implement compensating controls such as disabling unnecessary X server features or restricting access to X server sockets.
- Conduct regular security audits and vulnerability scans focusing on legacy systems.
- Plan for migration to supported, updated operating system versions to reduce exposure to legacy vulnerabilities.
Description
A out-of-bounds write flaw was found in the xorg-x11-server. This issue occurs due to an incorrect calculation of a buffer offset when copying data stored in the heap in the XIChangeDeviceProperty function in Xi/xiproperty.c and in RRChangeOutputProperty function in randr/rrproperty.c, allowing for possible escalation of privileges or denial of service.
References
- access.redhat.com/errata/RHSA-2023:6802 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:6808 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7373 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7388 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7405 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7428 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7436 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7526 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7533 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0010 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0128 (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-2023-5367 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2243091 (opens in a new tab)
- lists.x.org/archives/xorg-announce/2023-October/003430.html (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/2WS5E7H4A5J3U5YBCTMRPQVGWK5LVH7D/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/3RK66CXMXO3PCPDU3GDY5FK4UYHUXQJT/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/4YBK3I6SETHETBHDETFWM3VSZUQICIDV/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/AKKIE626TZOOPD533EYN47J4RFNHZVOP/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/HO2Q2NP6R62ZRQQG3XQ4AXUT7J2EKKKY/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/L2RMNR4235YXZZQ2X7Q4MTOZDMZ7BBQU/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SEDJN4VFN57K5POOC7BNVD6L6WUUCSG6/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/SN6KV4XGQJRVAOSM5C3CWMVAXO53COIP/ (opens in a new tab)
- lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TJXNI4BXURC2BKPNAHFJK3C5ZETB7PER/ (opens in a new tab)
- security.gentoo.org/glsa/202401-30 (opens in a new tab)
- security.netapp.com/advisory/ntap-20231130-0004/ (opens in a new tab)
- debian.org/security/2023/dsa-5534 (opens in a new tab)
- lists.debian.org/debian-lts-announce/2023/10/msg00036.html (opens in a new tab)