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, 08:30 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
1. Apply official patches from Red Hat as soon as they become available through Extended Lifecycle Support channels. 2. Restrict local access to systems running RHEL 6 Extended Lifecycle Support, limiting user accounts and enforcing strict access controls. 3. Monitor logs and system behavior for unusual activity related to X server property changes or crashes. 4. Consider isolating legacy systems from critical network segments to reduce risk of lateral movement. 5. Where patching is delayed, implement compensating controls such as disabling unnecessary X server features or restricting access to X server sockets. 6. Conduct regular security audits and vulnerability scans focusing on legacy systems. 7. 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)