CVE-2023-4004: Red Hat Enterprise Linux 8 · Use After Free
Affects Red Hat Enterprise Linux 8Source CVE Database V5
Not known to be exploited · CVSS 7.8 High.
Data as of 25 Oct 2026, 19:02 UTC
- EPSS
- 0.9% chance of exploitation in 30 days – higher than 59% 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 31 Jul 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 2026-10-25.
What to do
AI-suggested
1. Apply official Red Hat patches and kernel updates as soon as they become available to remediate the vulnerability. 2. Restrict local user access to trusted personnel only and enforce the principle of least privilege to minimize the number of users who can trigger the flaw. 3. Monitor system logs and kernel crash reports for signs of exploitation attempts or unusual behavior related to netfilter or nftables operations. 4. Employ kernel hardening techniques such as SELinux or AppArmor to limit the impact of potential privilege escalations. 5. Use security tools to audit and control nftables configurations and usage, ensuring no unauthorized or malformed rules exist. 6. For environments where immediate patching is not feasible, consider isolating vulnerable systems or disabling nftables features if operationally possible, understanding the trade-offs involved. 7. Maintain up-to-date backups and incident response plans to quickly recover from potential exploitation events. 8. Educate system administrators about the vulnerability and encourage vigilance for suspicious local activity.
Description
A use-after-free flaw was found in the Linux kernel's netfilter in the way a user triggers the nft_pipapo_remove function with the element, without a NFT_SET_EXT_KEY_END. This issue could allow a local user to crash the system or potentially escalate their privileges on the system.
References
- access.redhat.com/errata/RHSA-2023:4961 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:4962 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:4967 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5069 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5091 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5093 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5221 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5244 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5255 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5548 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:5627 (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-2023:7417 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7431 (opens in a new tab)
- access.redhat.com/errata/RHSA-2023:7434 (opens in a new tab)
- access.redhat.com/security/cve/CVE-2023-4004 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2225275 (opens in a new tab)
- patchwork.ozlabs.org/project/netfilter-devel/patch/20230719190824.21196-1-fw@strlen.de/ (opens in a new tab)
- packetstormsecurity.com/files/175072/Kernel-Live-Patch-Security-Notice-LSN-0098-1.html (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)
- security.netapp.com/advisory/ntap-20231027-0001/ (opens in a new tab)
- debian.org/security/2023/dsa-5480 (opens in a new tab)
- debian.org/security/2023/dsa-5492 (opens in a new tab)