CVE-2026-103427 (GCVE-0-2026-103427)

Vulnerability from cvelistv5 – Published: 2026-10-10 06:40 – Updated: 2026-10-11 12:13
VLAI
Title
Simple Membership <= 4.8.4 - Authenticated (Subscriber+) Stored Cross-Site Scripting via Country Field
Summary
The Simple Membership plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'country' parameter in all versions up to, and including, 4.8.4 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. Unauthenticated attackers may also exploit this vulnerability when the plugin's Enable Free Membership feature is turned on, as it permits anonymous front-end registration and profile submission.
Severity
6.4 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-11 12:12 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
Wordfence CNA under the mitre root
CNA scorecard C 65/100 over 2154 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
wpinsider-1 Simple Membership Affected: 0 , ≤ 4.8.4 (semver)
guessed Create a notification for this product.
Credits
Maciej Komorowski
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.