CVE-2021-41773Actively exploitedAdded to KEV 2021-11-03Known ransomware campaign use

Apache HTTP Server Path Traversal Vulnerability

Apache, HTTP Server

Description

Apache HTTP Server contains a path traversal vulnerability that allows an attacker to perform remote code execution if files outside directories configured by Alias-like directives are not under default �require all denied� or if CGI scripts are enabled. The original patch issued under this CVE ID is insufficient, please review remediation information under CVE-2021-42013.

CVSS severity for this advisory hasn't been enriched from NVD yet, check back shortly.

EPSS, exploit probability

Critical

100.0%

estimated chance of real-world exploitation in the next 30 days, higher than 100.0% of every CVE FIRST.org scores

Refreshed 10/28/2026, via FIRST.org's EPSS model, not CVSS, this measures likelihood of exploitation, not how severe it would be.

Required action

Apply updates per vendor instructions.

CISA-recommended due date: 2021-11-17

CWE-22

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