CVE-2021-42013
highpriority · act · 90OT risk · criticalKEV · exploitedEPSS 1.000 · 100 %ileexploit · weaponizedDEEURUUSadded 2021-11-03remediate by 2021-11-17
required action Apply updates per vendor instructions.
EPSS · scored 2026-10-26
Apache HTTP Server Path Traversal Vulnerability
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
ATT&CK techniques
ATT&CK techniques this enables or maps to.
exploits (42)
Public proof-of-concept and weaponised exploit code.
- exploit/multi/http/apache_normalize_path_rceApache 2.4.49/2.4.50 Traversal RCEweaponized · metasploit
- EDB-50406Apache HTTP Server 2.4.50 - Path Traversal & Remote Code Execution (RCE)functional · exploit_db
- EDB-50512Apache HTTP Server 2.4.50 - Remote Code Execution (RCE) (3)functional · exploit_db
- auxiliary/scanner/http/apache_normalize_pathApache 2.4.49/2.4.50 Traversal RCE scannerfunctional · metasploit
affected products (31)
Products and version ranges known to be affected.
advisories (2)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2024-1591Juniper JUNOS: Mehrere SchwachstellenDeutsch2024-07-10csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Juniper JUNOS ausnutzen, um einen Denial of Service zu verursachen, Informationen offenzulegen, Privilegien zu erweitern und Sicherheitsmechanismen inklusive zu umgehen.
- BIT-apache-2021-42013Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)2024-03-06vendor · osvUS
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.
also known as (4)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (105)
External citations — patches, advisories, analysis.
- http://jvn.jp/en/jp/JVN51106450/index.htmlcnnvd
- http://www.openwall.com/lists/oss-security/2021/10/07/6cnnvd
- http://www.openwall.com/lists/oss-security/2021/10/08/1cnnvd
- http://www.openwall.com/lists/oss-security/2021/10/08/2cnnvd
- http://www.openwall.com/lists/oss-security/2021/10/08/3cnnvd
- http://www.openwall.com/lists/oss-security/2021/10/08/4cnnvd
- http://www.openwall.com/lists/oss-security/2021/10/08/5cnnvd
- http://www.openwall.com/lists/oss-security/2021/10/08/6cnnvd
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