CVE-2023-42753: Red Hat Enterprise Linux 7 · Out-of-bounds Write
Affects Red Hat Enterprise Linux 7Source CVE Database V5
Not known to be exploited · CVSS 7.0 High.
Data as of 26 Oct 2026, 17:16 UTC
- EPSS
- 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 25 Sep 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
Organizations should prioritize applying the official Red Hat patches addressing CVE-2023-42753 as soon as they become available. Until patches are deployed, restrict local user access to trusted personnel only and enforce strict user privilege separation. Employ kernel hardening techniques such as SELinux policies to limit the impact of potential exploits. Monitor system logs and kernel messages for unusual behavior indicative of exploitation attempts. Regularly audit user accounts and remove unnecessary local accounts to reduce attack surface. Consider deploying intrusion detection systems capable of detecting anomalous kernel activity. For environments where patching is delayed, isolating vulnerable systems from untrusted users and networks can reduce risk. Finally, maintain up-to-date backups to enable recovery in case of system compromise or crashes.
Description
An array indexing vulnerability was found in the netfilter subsystem of the Linux kernel. A missing macro could lead to a miscalculation of the `h->nets` array offset, providing attackers with the primitive to arbitrarily increment/decrement a memory buffer out-of-bound. This issue may allow a local user to crash the system or potentially escalate their privileges on the system.
References
- access.redhat.com/errata/RHSA-2023:7370 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7379 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7382 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7389 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7411 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7418 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7539 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7558 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0089 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0113 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0134 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0340 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0346 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0347 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0371 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0376 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0378 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0402 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0403 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0412 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0461 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0562 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0563 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0593 (opens in a new tab)
- access.redhat.com/errata/RHSA-2024:0999 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2023-42753 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2239843 (opens in a new tab)
- seclists.org/oss-sec/2023/q3/216 (opens in a new tab)
- packetstormsecurity.com/files/175963/Kernel-Live-Patch-Security-Notice-LSN-0099-1.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2023/10/msg00027.html (opens in a new tab)
- lists.debian.org/debian-lts-announce/2024/01/msg00004.html (opens in a new tab)
- openwall.com/lists/oss-security/2023/09/22/10 (opens in a new tab)