CVE Database · CVE-2021-41773
CVSS v3.1
9.8
EPSS
99.99%
Published
Oct 5, 2021
Modified
Feb 17, 2026
CISA Known Exploited Vulnerability
Added: 2021-11-03 · Due: 2021-11-17
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Public PoC / Exploit (12)
All weaponized →Links to public security research (Exploit-DB, Nuclei, Trickest, GitHub) for defensive use only.
Description
A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. 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 is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.
CVSS Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HWeaknesses (CWE)
Affected Products (7)
References (20)