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CVE Record

CVE-2023-6882: Simple Membership <= 4.3.8 - Reflected Cross-Site Scripting Vulnerability via environment_mode

The Simple Membership plugin for WordPress is vulnerable to Reflected Cross-Site Scripting via the ‘environment_mode’ parameter in all versions up to, and including, 4.3.8 due to insufficient input sanitization and output escaping. This makes it possible for unauthenticated attackers to inject arbitrary web scripts in pages that execute if they can successfully trick a user into performing an action such as clicking on a link.

MediumCVSS 6.1Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

CVE-2023-6882 affects the Simple Membership WordPress plugin through reflected cross-site scripting in the environment_mode parameter. An unauthenticated attacker would still need to trick a user into clicking a crafted link. Successful exploitation could expose user data or alter browser-visible actions in that user’s session.

Executive priority

Treat as a near-term WordPress hygiene fix, not an emergency unless the plugin protects sensitive member workflows or administrators are frequently targeted.

Technical view

The issue is CWE-79 reflected XSS caused by insufficient sanitization and output escaping of environment_mode in Simple Membership versions up to and including 4.3.8. CVSS 3.1 is 6.1, network-reachable, low complexity, no privileges required, with user interaction required and changed scope.

Likely exposure

Exposure is limited to WordPress sites running Simple Membership at version 4.3.8 or earlier. The bundle does not identify other affected products or hosted services.

Exploitation context

The source bundle does not show CISA KEV listing or other evidence of active exploitation. Attack success depends on social engineering a user into following a malicious link.

Researcher notes

Evidence supports reflected XSS only. Do not assume stored XSS, authentication bypass, data theft, or active exploitation from the provided sources. The affected-version metadata is sparse, so validate against vendor records.

Mitigation direction

  • Inventory WordPress sites for Simple Membership plugin usage and version.
  • Move affected installations off versions 4.3.8 and earlier, following vendor guidance.
  • Review the referenced WordPress changeset before relying on remediation assumptions.
  • If upgrade timing is blocked, check vendor guidance for temporary controls.
  • Educate administrators not to follow unexpected plugin-setting or login links.

Validation and detection

  • Confirm each WordPress site’s Simple Membership version is not 4.3.8 or earlier.
  • Check application and security logs for suspicious requests containing environment_mode.
  • In staging, verify environment_mode output is escaped and cannot execute script content.
  • Confirm the referenced WordPress plugin changeset is included in the deployed build.
Prepared
Confidence
high
Sources
4

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-79: User-session and phishing behavior lookup

Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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.

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cve · low confidence lookup

CVE-2023-6882 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
Medium
CVSS
6.1 (3.1)
Known Exploited
No
Published

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

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
3Source 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
6.1CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.1Medium
CVSS 3.1 vector shape for CVE-2023-6882Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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
wpinsider-1Simple Membership0unaffected
Weakness

CWE details

CWE-79

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