Critical severity · published Oct 7, 2021
CVE-2021-42013
Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)
RansomwareIn wildKEV
9.8
CVSS
100%
EPSS
Yes
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)100.0% · higher than 100% of CVEs
Exploited in the wildYes
CISA KEVListed Nov 3, 2021
Federal remediation dueNov 17, 2021
Ransomware campaign useKnown
Affected products
Which versions
HS
HTTP Server · Apache
Apache HTTP Server 2.4.49; Apache HTTP Server 2.4.50 · source: vendor, NVD, KEV
CB
Cloud Backup · Netapp
All versions, or not specified · source: NVD
FE
Fedora · Fedoraproject
34; 35 · source: NVD
IE
Instantis Enterprisetrack · Oracle
17.1; 17.2; 17.3 · source: NVD
JE
JD Edwards Enterpriseone Tools · Oracle
before 9.2.6.0 · source: NVD
SB
Secure Backup · Oracle
before 18.1.0.1.0 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-42013
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-42013
CISA KEV catalogue
https://www.cisa.gov/known-exploited-vulnerabilities-catalog
x_refsource_MISC
https://httpd.apache.org/security/vulnerabilities_24.html
mailing-list
https://lists.apache.org/thread.html/r7c795cd45a3384d4d27e57618a215b0ed19cb6ca8eb070061ad5d837%40%3Cannounce.apache.org%3E
mailing-list
https://lists.apache.org/thread.html/rb5b0e46f179f60b0c70204656bc52fcb558e961cb4d06a971e9e3efb%40%3Cusers.httpd.apache.org%3E
mailing-list
http://www.openwall.com/lists/oss-security/2021/10/07/6
vendor-advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZ
third-party-advisory
http://jvn.jp/en/jp/JVN51106450/index.html
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