Actively exploited in the wild
Apache HTTP Server Path Traversal Vulnerability
Apache - HTTP Server · Listed in the CISA KEV since 2021-11-03. This indicates confirmed attacks in production environments.
Required action: Apply updates per vendor instructions.
CVE-2021-42013
CriticalCVSS 9.8KEVSummary
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.
Risk Assessment
The risk includes unauthorized access to files outside server directories and potential remote code execution, which could lead to full server compromise.
Recommendation
It is recommended to immediately upgrade Apache HTTP Server to version 2.4.51 or later, which contains the complete fix, and review configuration for unprotected directories.
Other vulnerabilities in Apache HTTP Server
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- CVE-2024-27316Medium
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Original NVD description (English source)
It was found that the fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue only affects Apache 2.4.49 and Apache 2.4.50 and not earlier versions.