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CVE-2021-24964 - Before 4 Plugin

CVE-2021-24964

The LiteSpeed Cache WordPress plugin before 4.4.4 does not properly verify that requests are coming from QUIC.cloud servers, allowing attackers to make requests to certain endpoints by using a specific X-Forwarded-For header value. In addition, one of the endpoint could be used to set CSS code if a setting is enabled, which will then be output in some pages without being sanitised and escaped. Combining those two issues, an unauthenticated attacker could put Cross-Site Scripting payloads in pages visited by users.

CVE-2021-24964

MEDIUM CVSS 6.1 Published 2022-01-03 Updated 2025-05-22
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 2
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. 2022-01-03 CVE published and first recorded in the threat feed.
  2. 2025-05-22 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 02:59 UTC)

Technical Summary

The LiteSpeed Cache WordPress plugin before 4.4.4 does not properly verify that requests are coming from QUIC.cloud servers, allowing attackers to make requests to certain endpoints by using a specific X-Forwarded-For header value. In addition, one of the endpoint could be used to set CSS code if a setting is enabled, which will then be output in some pages without being sanitised and escaped. Combining those two issues, an unauthenticated attacker could put Cross-Site Scripting payloads in pages visited by…

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 4 PLUGIN · before-4 Affected: < 4.4.4 Fixed in: 4.4.4
Litespeed Cache PLUGIN · litespeed-cache Affected: < 4.4.4 Fixed in: 4.4.4
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