CVE intelligence and bounded remediation
CVE-2024-3961 — Convertkit Convertkit - Email Marketing, Email Newsletter And Landing P… security vulnerability
The ConvertKit – Email Newsletter, Email Marketing, Subscribers and Landing Pages plugin for WordPress is vulnerable to unauthorized modification of data due to a missing capability check on the tag_subscriber function in all versions up to, and including, 2.4.9. This makes it possible for unauthenticated attackers to subscribe users to tags. Financial damages may occur to site owners if their API quota is exceeded.
- Severity
- Medium
- CVSS
- 5.3 (3.1)
- Published
- 2024-06-21
- CISA KEV
- Not currently listed
- Ecosystem
- php/wordpress
- Weaknesses
- CWE-862
Affected products
- convertkit / convertkit_-_email_marketing,_email_newsletter_and_landing_pages
Matched remediation archetype
Authorization bypass, IDOR, and cross-tenant access
This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.
Check exposure
- Map object and action authorization checks across API, UI, batch, import/export, and background-job paths.
- Identify tenant, ownership, role, and policy boundaries for affected resources and administrative operations.
- Use synthetic fixtures to compare intended access matrices without accessing another user's real data.
Remediate safely
- Enforce server-side authorization at each resource access and state transition using the authenticated principal and trusted tenant context.
- Scope data queries by tenant and ownership; treat client-supplied identifiers, roles, and policy claims as untrusted.
- Add deny-by-default policy tests for horizontal and vertical access across every affected transport.
Authoritative sources
Complete CVE record and remediation plan
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