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CVE-2021-24977 - Before 6 Plugin

CVE-2021-24977

The Use Any Font | Custom Font Uploader WordPress plugin before 6.2.1 does not have any authorisation checks when assigning a font, allowing unauthenticated users to sent arbitrary CSS which will then be processed by the frontend for all users. Due to the lack of sanitisation and escaping in the backend, it could also lead to Stored XSS issues

CVE-2021-24977

MEDIUM CVSS 6.1 Published 2022-02-28 Updated 2026-01-13
AI Risk Elevated (59/100) Active Exploit: No strong signal Published Exploit: No public exploit references Priority: P3 Priority
Severity Band MEDIUM
CVSS Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Affected Components 3
Reference Links 1
AI Risk Engine Elevated (59/100)
Exploitability Medium
Active Exploitation No strong signal
Published Exploit Status No public exploit references

Threat Timeline

  1. 2022-02-28 CVE published and first recorded in the threat feed.
  2. 2026-01-13 Record updated with latest vulnerability metadata.
  3. 2026-04-12 AI technical context refreshed for mitigation and impact guidance.
  4. Now Monitoring for follow-up changes, linked references, and new related CVEs.

AI Context

Machine-generated threat intelligence

AI Updated 4 days ago

AI enriched 4 days ago (2026-04-12 02:30 UTC)

Technical Summary

The Use Any Font | Custom Font Uploader WordPress plugin before 6.2.1 does not have any authorisation checks when assigning a font, allowing unauthenticated users to sent arbitrary CSS which will then be processed by the frontend for all users. Due to the lack of sanitisation and escaping in the backend, it could also lead to Stored XSS issues

Potential Impact

Severity is MEDIUM (CVSS 6.1). Depending on deployment context, affected components may be exposed to unauthorized actions or data integrity risk.

Exploitability Assessment

Exploitability is assessed as Medium based on low-bar exploit prerequisites.

Primary risk drivers: low-bar exploit prerequisites

Mitigation Recommendations

Validate affected product versions, prioritize patching, and monitor references for vendor remediation guidance. If immediate patching is not possible, apply compensating controls and limit exposure of vulnerable surfaces.

Detection & Monitoring

Track authentication anomalies, unexpected file writes, and suspicious plugin API activity around affected components.

Business Impact Lens

AI risk score 59/100 (Elevated, Medium) with priority P3 Priority. Prioritize remediation where affected components process customer data, admin sessions, or Internet-exposed workflows.

Affected Products

Before 6 PLUGIN · before-6 Affected: < 6.2.1 Fixed in: 6.2.1
Custom Font Uploader PLUGIN · custom-font-uploader Affected: < 6.2.1 Fixed in: 6.2.1
Use Any Font PLUGIN · use-any-font Affected: < 6.2.1 Fixed in: 6.2.1
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