WordPress security changelog
HIGH CVE-2021-47977 Deferred

Malware Security and Bruteforce Firewall: Filesystem traversal

Malware Security and Bruteforce Firewall is affected by filesystem traversal. The vulnerable path is reachable without authentication. A crafted path can escape the intended directory and reach files or directories elsewhere on the server. The published affected range is <= 4.20.72.

CVE / CNA score 8.7 CVSS 4.0 · disclosure@vulncheck.com
NVD score Pending NVD has not published its own CVSS assessment.
Component
Malware Security and Bruteforce Firewall
Plugin slug
anti-malware-security-and-bruteforce-firewall
Affected
<= 4.20.72
Safe version
> 4.20.72
Published
May 16, 2026
Weakness
CWE-22 — Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

This CVE was published May 16, 2026 and is one of 1 known issue for this plugin.

Update, patch or deactivate.

Update Malware Security and Bruteforce Firewall to a release after 4.20.72, or disable and remove it until a fixed version is available.

A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.

Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.

Technical description

WordPress Plugin Anti-Malware Security and Bruteforce Firewall 4.20.59 contains a directory traversal vulnerability that allows unauthenticated attackers to read arbitrary files by manipulating the file parameter. Attackers can send requests to the duplicator_download action via admin-ajax.php with path traversal sequences to access sensitive system files outside the intended directory.

CVE / CNA vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary and upstream sources