CVE-2021-42013

critical
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Description

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.

References

https://httpd.apache.org/security/vulnerabilities_24.html

https://lists.apache.org/thread.html/[email protected]%3Cannounce.apache.org%3E

https://lists.apache.org/thread.html/[email protected]%3Cusers.httpd.apache.org%3E

http://www.openwall.com/lists/oss-security/2021/10/07/6

https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ

http://jvn.jp/en/jp/JVN51106450/index.html

http://www.openwall.com/lists/oss-security/2021/10/08/1

https://lists.apache.org/thread.html/[email protected]%3Ccvs.httpd.apache.org%3E

http://www.openwall.com/lists/oss-security/2021/10/08/2

http://www.openwall.com/lists/oss-security/2021/10/08/4

http://www.openwall.com/lists/oss-security/2021/10/08/3

http://www.openwall.com/lists/oss-security/2021/10/08/6

http://www.openwall.com/lists/oss-security/2021/10/08/5

http://www.openwall.com/lists/oss-security/2021/10/09/1

http://www.openwall.com/lists/oss-security/2021/10/11/4

https://lists.fedoraproject.org/archives/list/[email protected]/message/RMIIEFINL6FUIOPD2A3M5XC6DH45Y3CC/

http://packetstormsecurity.com/files/164501/Apache-HTTP-Server-2.4.50-Path-Traversal-Code-Execution.html

https://lists.fedoraproject.org/archives/list/[email protected]/message/WS5RVHOIIRECG65ZBTZY7IEJVWQSQPG3/

http://www.openwall.com/lists/oss-security/2021/10/15/3

http://www.openwall.com/lists/oss-security/2021/10/16/1

http://packetstormsecurity.com/files/164609/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.html

http://packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.html

https://security.netapp.com/advisory/ntap-20211029-0009/

http://packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.html

http://packetstormsecurity.com/files/165089/Apache-HTTP-Server-2.4.50-CVE-2021-42013-Exploitation.html

Details

Source: MITRE

Published: 2021-10-07

Updated: 2021-11-30

Type: CWE-22

Risk Information

CVSS v2

Base Score: 7.5

Vector: AV:N/AC:L/Au:N/C:P/I:P/A:P

Impact Score: 6.4

Exploitability Score: 10

Severity: HIGH

CVSS v3

Base Score: 9.8

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Impact Score: 5.9

Exploitability Score: 3.9

Severity: CRITICAL

Tenable Plugins

View all (6 total)

IDNameProductFamilySeverity
155600Apache HTTP Server 2.4.49 & 2.4.50 Path Traversal (CVE-2021-42013)NessusCGI abuses
critical
154188Amazon Linux AMI : httpd24 (ALAS-2021-1543)NessusAmazon Linux Local Security Checks
critical
154179Amazon Linux 2 : httpd (ALAS-2021-1716)NessusAmazon Linux Local Security Checks
critical
153983FreeBSD : Apache httpd -- Path Traversal and Remote Code Execution (d001c189-2793-11ec-8fb1-206a8a720317)NessusFreeBSD Local Security Checks
critical
153952Apache 2.4.49 < 2.4.51 Path Traversal VulnerabilityNessusWeb Servers
critical
113015Apache 2.4.49 < 2.4.51 Path TraversalWeb Application ScanningComponent Vulnerability
critical