CVE-2023-4385VulnerabilityPublished 16 Aug 2023Updated 20 Nov 2025

CVE-2023-4385: Red Hat Enterprise Linux 6 · NULL Pointer Dereference

Affects Red Hat Enterprise Linux 6Source 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: 0.2% chance of exploitation in 30 days – higher than 14% 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 16 Aug 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

To mitigate CVE-2023-4385, organizations should prioritize applying official patches from Red Hat once available to address the NULL pointer dereference in the JFS kernel code. Until patches are deployed, disabling the JFS file system module or avoiding its use can reduce exposure. Restricting local system access to trusted and authenticated users minimizes the risk of exploitation by unprivileged attackers. Employing host-based intrusion detection systems to monitor for unusual kernel crashes or suspicious local activity can provide early warning. For environments where upgrading is feasible, migrating from Red Hat Enterprise Linux 6 to a supported, updated version eliminates the vulnerability and improves overall security posture. Regular auditing of legacy systems and minimizing the attack surface by disabling unused kernel modules are also recommended. Finally, implementing strict access controls and monitoring local user activities can help detect and prevent exploitation attempts.

Description

A NULL pointer dereference flaw was found in dbFree in fs/jfs/jfs_dmap.c in the journaling file system (JFS) in the Linux Kernel. This issue may allow a local attacker to crash the system due to a missing sanity check.

Impact

The primary impact of CVE-2023-4385 is a denial of service through system crashes caused by kernel panics. For European organizations, this can disrupt critical services, especially in sectors relying on legacy Red Hat Enterprise Linux 6 systems with JFS enabled, such as industrial control, telecommunications, or government infrastructure. Although the vulnerability does not allow privilege escalation or data compromise, repeated or targeted exploitation could lead to significant operational downtime and potential loss of availability for essential applications. Organizations with limited ability to upgrade legacy systems may face increased risk. The requirement for local access limits remote exploitation, but insider threats or attackers who have gained initial footholds could leverage this flaw to escalate disruption. The lack of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits over time. The impact is thus moderate but relevant for environments where uptime and system stability are critical.

References

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 20 Nov 2025, 18:41 UTC

Technical details

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