CVE-2023-42754VulnerabilityPublished 5 Oct 2023Updated 6 Nov 2025

CVE-2023-42754: Red Hat Enterprise Linux 8 · NULL Pointer Dereference

Affects Red Hat Enterprise Linux 8Source CVE Database V5

Not known to be exploited · CVSS 5.5 Medium.

Data as of 25 Oct 2026, 19:02 UTC

CVSS 3.1 base score

5.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.4% chance of exploitation in 30 days – higher than 36% 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:N/I:N/A:H

Attack Vector: Local
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: High

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Local: The vulnerable component is not bound to the network stack and the attacker’s path is via read/write/execute capabilities. Either: the attacker exploits the vulnerability by accessing the target system locally (e.g., keyboard, console), or remotely (e.g., SSH); or the attacker relies on User Interaction by another person to perform actions required to exploit the vulnerability (e.g., tricking a legitimate user into opening a malicious document).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: High: There is total loss of availability, resulting in the attacker being able to fully deny access to resources in the impacted component; this loss is either sustained (while the attacker continues to deliver the attack) or persistent (the condition persists even after the attack has completed). Alternatively, the attacker has the ability to deny some availability, but the loss of availability presents a direct, serious consequence to the impacted component (e.g., the attacker cannot disrupt existing connections, but can prevent new connections; the attacker can repeatedly exploit a vulnerability that, in each instance of a successful attack, leaks a only small amount of memory, but after repeated exploitation causes a service to become completely unavailable).

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 5 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 2026-10-25.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

AI-suggested

1. Apply official Red Hat patches as soon as they are released to address the NULL pointer dereference in the kernel IPv4 stack. 2. Restrict CAP_NET_ADMIN privileges strictly to trusted administrators and minimize the number of users or containers granted this capability. 3. Audit and monitor usage of ipvs and related network routing/load balancing configurations to detect unusual or unauthorized changes. 4. Employ kernel crash monitoring and automated recovery mechanisms to reduce downtime in case of exploitation. 5. Use security frameworks like SELinux or AppArmor to enforce strict access controls on network-related kernel operations. 6. In containerized environments, limit capabilities granted to containers and avoid granting CAP_NET_ADMIN unless absolutely necessary. 7. Maintain up-to-date inventory of systems running Red Hat Enterprise Linux 8 and prioritize patching on critical infrastructure and exposed systems. 8. Conduct regular security training for administrators on the risks of privilege misuse and kernel vulnerabilities. 9. Consider network segmentation to isolate critical systems and reduce the impact of local privilege exploitation. 10. Monitor vendor advisories and CVE databases for updates or emerging exploit reports related to this vulnerability.

Description

A NULL pointer dereference flaw was found in the Linux kernel ipv4 stack. The socket buffer (skb) was assumed to be associated with a device before calling __ip_options_compile, which is not always the case if the skb is re-routed by ipvs. This issue may allow a local user with CAP_NET_ADMIN privileges to crash the system.

Impact

For European organizations, the primary impact of CVE-2023-42754 is a potential denial of service caused by a kernel crash. This can disrupt critical services running on Red Hat Enterprise Linux 8 servers, especially those leveraging ipvs for load balancing or routing. Organizations with multi-tenant environments, container orchestration platforms, or network management systems granting CAP_NET_ADMIN privileges to local users or containers are at higher risk. The disruption could affect availability of web services, internal applications, or infrastructure components, leading to operational downtime and potential financial losses. Since the vulnerability does not compromise confidentiality or integrity, data breaches are unlikely. However, repeated exploitation could degrade trust in system reliability. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially in targeted attacks or insider threat scenarios. European sectors relying heavily on Linux servers for critical infrastructure, such as finance, telecommunications, and government, may face increased exposure if patches are not applied promptly.

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 6 Nov 2025, 20:59 UTC

Technical details

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