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CVE Record

CVE-2023-27459: WordPress User Registration plugin <= 2.3.2.1 - Authenticated PHP Object Injection vulnerability

Deserialization of Untrusted Data vulnerability in WPEverest User Registration.This issue affects User Registration: from n/a through 2.3.2.1.

HighCVSS 7.4Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2023-27459 affects the WordPress User Registration plugin by WPEverest through version 2.3.2.1. An authenticated user may be able to trigger unsafe data deserialization, potentially affecting confidentiality, integrity, and availability. The business risk is highest for public WordPress sites with open registration or many low-trust accounts.

Executive priority

Treat as high priority for public WordPress properties, especially where users can self-register. Schedule remediation promptly, but do not claim emergency active exploitation based on the supplied sources.

Technical view

The issue is CWE-502 deserialization of untrusted data in the user-registration package. The CVSS 3.1 score is 7.4, with network attack vector, low complexity, low privileges required, no user interaction, changed scope, and low C/I/A impact.

Likely exposure

Exposure is limited to WordPress deployments running WPEverest User Registration through 2.3.2.1. Sites with public signup, customer portals, or many contributor-level users have higher practical exposure because exploitation requires authenticated access.

Exploitation context

The source bundle does not show CISA KEV listing or confirmed active exploitation. The CVSS vector indicates remote authenticated exploitation with low complexity and no victim interaction, so affected internet-facing sites should not treat this as theoretical.

Researcher notes

Evidence identifies authenticated PHP object injection via unsafe deserialization but does not include exploit details or a named fixed version in the provided bundle. Validate reachability in authorized environments only and track vendor advisory updates.

Mitigation direction

  • Inventory WordPress sites using the user-registration plugin.
  • Prioritize vendor-guided updates for versions through 2.3.2.1.
  • Check WPEverest and Patchstack guidance for the fixed release.
  • Remove stale or unnecessary WordPress user accounts.
  • Restrict registration on affected sites until remediated.

Validation and detection

  • Confirm installed User Registration plugin versions across WordPress sites.
  • Flag any deployment running version 2.3.2.1 or earlier.
  • Review whether public or low-trust user registration is enabled.
  • Check vendor advisories before marking the issue remediated.
  • Review recent authenticated activity for unusual behavior.
Prepared
Confidence
medium
Sources
3

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · medium confidence lookup

CWE-502: Code execution behavior lookup

Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2023-27459 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
7.4 (3.1)
Known Exploited
No
Published

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

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
2Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7.4CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:L3.13.7Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

7.4High
CVSS 3.1 vector shape for CVE-2023-27459Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
WPEverestUser Registrationuser-registration, n/aunaffected
Weakness

CWE details

CWE-502

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.