AttackerKBAKB:4BB9D3C7-37EF-4B65-B2A8-550AFC30664CCVE-2021-41773
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:P/I:P/A:P
0.974 High
EPSS
Percentile
99.9%
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.
Recent assessments:
zeroSteiner at October 05, 2021 3:29pm UTC reported:
Apache doesn’t typically run with root privileges in most environments so the value of this vulnerability will largely be in using it to leak application-specific secrets such as signing keys, database connection strings, source code etc. Path traversal vulnerabilities are among the easiest to exploit and involve no type of corruption, making them very reliable and safe to use multiple times.
There will likely be evidence within the Apache access logs of exploitation. Filtering on the HTTP status code could also provide insight into what files the attacker was able to successfully leak.
noraj at March 31, 2022 6:23pm UTC reported:
Apache doesn’t typically run with root privileges in most environments so the value of this vulnerability will largely be in using it to leak application-specific secrets such as signing keys, database connection strings, source code etc. Path traversal vulnerabilities are among the easiest to exploit and involve no type of corruption, making them very reliable and safe to use multiple times.
There will likely be evidence within the Apache access logs of exploitation. Filtering on the HTTP status code could also provide insight into what files the attacker was able to successfully leak.
Assessed Attacker Value: 5
Assessed Attacker Value: 5Assessed Attacker Value: 5
References
packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal-Remote-Code-Execution.html
packetstormsecurity.com/files/164418/Apache-HTTP-Server-2.4.49-Path-Traversal.html
packetstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.html
packetstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.html
www.openwall.com/lists/oss-security/2021/10/05/2
www.openwall.com/lists/oss-security/2021/10/07/1
www.openwall.com/lists/oss-security/2021/10/07/6
www.openwall.com/lists/oss-security/2021/10/08/1
www.openwall.com/lists/oss-security/2021/10/08/2
www.openwall.com/lists/oss-security/2021/10/08/3
www.openwall.com/lists/oss-security/2021/10/08/4
www.openwall.com/lists/oss-security/2021/10/08/5
www.openwall.com/lists/oss-security/2021/10/08/6
www.openwall.com/lists/oss-security/2021/10/09/1
www.openwall.com/lists/oss-security/2021/10/11/4
www.openwall.com/lists/oss-security/2021/10/15/3
www.openwall.com/lists/oss-security/2021/10/16/1
cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-41773
httpd.apache.org/security/vulnerabilities_24.html
lists.apache.org/thread.html/r17a4c6ce9aff662efd9459e9d1850ab4a611cb23392fc68264c72cb3@%3Ccvs.httpd.apache.org%3E
lists.apache.org/thread.html/r6abf5f2ba6f1aa8b1030f95367aaf17660c4e4c78cb2338aee18982f@%3Cusers.httpd.apache.org%3E
lists.apache.org/thread.html/r7c795cd45a3384d4d27e57618a215b0ed19cb6ca8eb070061ad5d837@%3Cannounce.apache.org%3E
lists.apache.org/thread.html/r98d704ed4377ed889d40479db79ed1ee2f43b2ebdd79ce84b042df45@%3Cannounce.apache.org%3E
lists.apache.org/thread.html/rb5b0e46f179f60b0c70204656bc52fcb558e961cb4d06a971e9e3efb@%3Cusers.httpd.apache.org%3E
lists.fedoraproject.org/archives/list/[email protected]/message/RMIIEFINL6FUIOPD2A3M5XC6DH45Y3CC/
lists.fedoraproject.org/archives/list/[email protected]/message/WS5RVHOIIRECG65ZBTZY7IEJVWQSQPG3/
security.gentoo.org/glsa/202208-20
security.netapp.com/advisory/ntap-20211029-0009/
tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ
www.oracle.com/security-alerts/cpujan2022.html
Related
9.8 High
CVSS3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
HIGH
Availability Impact
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5 High
CVSS2
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
AV:N/AC:L/Au:N/C:P/I:P/A:P
0.974 High
EPSS
Percentile
99.9%