CVE-2023-6855VulnerabilityPublished 11 Jan 2024Updated 3 Jun 2025

CVE-2023-6855: Paid Memberships Pro (WordPress plugin) · Missing Authorization

Affects Paid Memberships Pro (WordPress plugin)Source CVE Database V5

Not known to be exploited · CVSS 5.3 Low.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

5.3Low

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

EPSS: 0.5% chance of exploitation in 30 days – higher than 43% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
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: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
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 Jan 2024
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

Affected software

Product	Affected	Fixed in
strangerstudios Paid Memberships Pro – Content Restriction, User Registration, & Paid Subscriptions	Affected *	Fixed in–

AI-suggested

European organizations should immediately audit their WordPress installations to identify if the Paid Memberships Pro plugin is in use and verify the version. Until an official patch is released, it is advisable to implement temporary access restrictions on the REST API endpoints related to membership management, for example by using web application firewalls (WAFs) or custom code to enforce strict authorization checks. Monitoring and logging REST API calls for suspicious activity can help detect exploitation attempts early. Organizations should also consider disabling or restricting the plugin’s REST API functionality if it is not essential. Regular backups of membership data should be maintained to enable recovery in case of unauthorized changes. Additionally, organizations should subscribe to vendor advisories and security mailing lists to promptly apply any forthcoming patches. For sites with high security requirements, consider isolating membership management functions or migrating to alternative plugins with stronger security postures.

Description

The Paid Memberships Pro – Content Restriction, User Registration, & Paid Subscriptions plugin for WordPress is vulnerable to unauthorized modification of membership levels created by the plugin due to an incorrectly implemented capability check in the pmpro_rest_api_get_permissions_check function in all versions up to 2.12.5 (inclusive). This makes it possible for unauthenticated attackers to change membership levels including prices.

Impact

For European organizations using the Paid Memberships Pro plugin on their WordPress sites, this vulnerability poses a risk to the integrity of their membership management systems. Attackers could manipulate membership levels, potentially granting unauthorized access to premium content or services without payment, or altering pricing structures to cause financial loss or reputational damage. This could lead to revenue loss, customer trust erosion, and compliance issues, especially under regulations like GDPR if personal data is indirectly affected through unauthorized membership changes. While the vulnerability does not directly compromise confidentiality or availability, the unauthorized modification of membership data can disrupt business operations and customer relationships. Organizations relying heavily on subscription-based models or membership-driven content in sectors such as media, education, or professional services in Europe should be particularly cautious. The lack of required authentication and user interaction makes exploitation easier, increasing the risk of automated or opportunistic attacks.

CWE-862Missing Authorization (opens in a new tab)
Class weaknessLikelihood of exploit: HighCWE Top 25 (2025): #4OWASP Top 10 A01:2025: Broken Access Control (opens in a new tab)
The product does not perform an authorization check when an actor attempts to access a resource or perform an action.
Architecture and Design
Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries.
Architecture and Design
Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records.
Architecture and Design · Libraries or Frameworks
Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
OWASP Cheat Sheets
Authorization (opens in a new tab)
OWASP ASVS 4.0.3
V8.3.8 (opens in a new tab)
V13.4.2 (opens in a new tab)
V7.2.2 (opens in a new tab)
Attack patterns
Exploitation of Thunderbolt Protection Flaws (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 4 Jul 2025, 15:40 UTC

WeaknessesCWE-862

Technical details

References

Community reviews

Related threats