VulnerabilityPublished 3 Oct 2023Updated 7 Nov 2025

CVE-2023-4732: Red Hat Enterprise Linux 8 · Race Condition Within a Thread

Affects Red Hat Enterprise Linux 8Source CVE Database V5

Not known to be exploited · CVSS 4.7 Medium.

Data as of 26 Oct 2026, 10:12 UTC

CVSS 3.1 base score

4.7Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 7% 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:N/I:N/A:H

Attack Vector: Local
Attack Complexity: High
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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
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 3 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.

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 or the CVSS exploit maturity 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

To mitigate CVE-2023-4732, organizations should: 1) Monitor Red Hat advisories closely and apply kernel patches as soon as they become available to address the race condition. 2) Restrict local user privileges rigorously, ensuring that only trusted users have shell or system access, reducing the attack surface. 3) Implement strict access controls and use multi-factor authentication to prevent unauthorized local access. 4) Employ system integrity monitoring and kernel crash detection tools to quickly identify and respond to kernel panics or unusual system behavior. 5) Consider deploying kernel hardening features such as SELinux or AppArmor to limit the impact of potential exploits. 6) Conduct regular audits of user accounts and privilege levels to minimize insider threat risks. 7) In virtualized or containerized environments, isolate workloads to prevent lateral movement from compromised local users. 8) Maintain up-to-date backups and incident response plans to recover quickly from potential DoS incidents.

Description

CVE-2023-4732 is a medium-severity race condition vulnerability in the memory management subsystem of the Linux kernel used by Red Hat Enterprise Linux 8. It arises from a flaw in the pfn_swap_entry_to_page function, where a local attacker can trigger a denial of service (DoS) by causing a kernel BUG due to improper handling of a pmd_t variable. Exploitation requires local user privileges and high attack complexity, with no user interaction needed. The vulnerability impacts system availability but does not affect confidentiality or integrity. No known exploits are currently reported in the wild. European organizations running Red Hat Enterprise Linux 8 should prioritize patching once updates are available to prevent potential service disruptions. Countries with significant enterprise Linux deployments and critical infrastructure relying on Red Hat are most at risk. Mitigation involves applying kernel patches promptly, restricting local user access, and monitoring for unusual system crashes related to memory management.

Impact

For European organizations, the primary impact of CVE-2023-4732 is the potential for denial of service on systems running Red Hat Enterprise Linux 8. This can disrupt critical business operations, especially in sectors relying heavily on Linux servers such as finance, telecommunications, government, and industrial control systems. The DoS could lead to downtime, loss of availability of key services, and increased operational costs due to system restarts and troubleshooting. Since the vulnerability requires local access, insider threats or compromised user accounts pose the greatest risk. The flaw does not allow data leakage or unauthorized data modification, so confidentiality and integrity impacts are minimal. However, availability disruptions in critical infrastructure could have cascading effects on dependent services and users. Organizations with large Red Hat deployments or those providing hosting and cloud services may face broader operational challenges if multiple systems are affected simultaneously.

References

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 14 Nov 2025, 13:48 UTC

Technical details

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