CVE-2023-39418VulnerabilityPublished 11 Aug 2023Updated 21 Nov 2025

CVE-2023-39418: Red Hat Enterprise Linux 8 · Insufficient Granularity of Access Control

Affects Red Hat Enterprise Linux 8Source CVE Database V5

Not known to be exploited · CVSS 3.1 Low.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

3.1Low

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

EPSS: 1.0% chance of exploitation in 30 days – higher than 65% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N

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

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

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
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: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 11 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 2026-10-26.

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-2023-39418, European organizations should take several specific steps beyond general best practices: 1) Conduct a thorough audit of existing row-level security policies in PostgreSQL, especially focusing on differences between INSERT, UPDATE, and SELECT policies to identify inconsistencies that could be exploited. 2) Temporarily restrict or monitor the use of the MERGE command in environments where RLS policies are critical until patches are applied. 3) Implement database activity monitoring and alerting for unusual MERGE operations or unexpected data insertions that violate policy expectations. 4) Apply principle of least privilege rigorously, ensuring that users with MERGE command execution rights are limited to trusted roles. 5) Stay current with Red Hat and PostgreSQL security advisories and promptly apply patches once available. 6) Consider additional compensating controls such as application-layer validation of data integrity and enhanced logging for forensic analysis. 7) Engage with database administrators and security teams to review and update incident response plans to include scenarios involving RLS bypass. These targeted actions will help reduce the risk of exploitation and maintain data integrity.

Description

A vulnerability was found in PostgreSQL with the use of the MERGE command, which fails to test new rows against row security policies defined for UPDATE and SELECT. If UPDATE and SELECT policies forbid some rows that INSERT policies do not forbid, a user could store such rows.

Impact

For European organizations, the impact of CVE-2023-39418 is primarily related to data integrity within PostgreSQL databases enforcing row-level security policies. Unauthorized insertion of rows that bypass UPDATE and SELECT restrictions could lead to inaccurate or unauthorized data being stored, potentially affecting business processes, reporting, or compliance with data governance policies. While the vulnerability does not expose confidential data or disrupt availability, the integrity compromise could be significant in regulated industries such as finance, healthcare, or government sectors where strict data access controls are mandated. The low CVSS score and lack of known exploits suggest limited immediate risk, but organizations with complex RLS configurations should consider the potential for misuse by low-privileged users or insider threats. The vulnerability could also complicate audit and compliance efforts if unauthorized data insertion goes undetected. Overall, the threat is moderate in scope but warrants attention in environments with stringent data access requirements.

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Exploitation evidence

What to do

Description

AI analysisMachine-generated, updated 21 Nov 2025, 07:25 UTC

Technical details

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