by Kastro
Paper/Archive/CVE-2021-42013

CVE-2021-42013

Apache Software Foundation Apache HTTP Server — Path Traversal and Remote Code Execution in Apache HTTP Server 2.4.49 and 2.4.50 (incomplete fix of CVE-2021-41773)

KEV · due 17 Novransomware useEPSS 100%public exploitSSVC actCVSS 9.8
critical.is priorityof 100
99
CVSS 9.8 (ADP)9.8 / 10 × 3029.4In CISA KEV+3030.0EPSS percentile 100.01.000 × 2020.0Exploit: SSVC active+1010.0SSVC exploitation: active+1010.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
Apache HTTP ServerApache HTTP Server 2.4.49–CNA
Apache HTTP ServerApache HTTP Server 2.4.50–CNA

Scores by source

CISA ADP9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: active · Automatable: yes · Technical impact: total

References

refhttpd.apache.org/security/vulnerabilities_24.htmlreflists.apache.org/thread.html/r7c795cd45a3384d4d27e57618a215b0ed19cb6ca8eb070061ad5d837%40%3Cannounce.apache.org%3Ereflists.apache.org/thread.html/rb5b0e46f179f60b0c70204656bc52fcb558e961cb4d06a971e9e3efb%40%3Cusers.httpd.apache.org%3Erefopenwall.com/lists/oss-security/2021/10/07/6advisorytools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-apache-httpd-pathtrv-LAzg68cZwriteupjvn.jp/en/jp/JVN51106450/index.htmlrefopenwall.com/lists/oss-security/2021/10/08/1reflists.apache.org/thread.html/r17a4c6ce9aff662efd9459e9d1850ab4a611cb23392fc68264c72cb3%40%3Ccvs.httpd.apache.org%3Erefopenwall.com/lists/oss-security/2021/10/08/2refopenwall.com/lists/oss-security/2021/10/08/3refopenwall.com/lists/oss-security/2021/10/08/4refopenwall.com/lists/oss-security/2021/10/08/6refopenwall.com/lists/oss-security/2021/10/08/5refopenwall.com/lists/oss-security/2021/10/09/1refopenwall.com/lists/oss-security/2021/10/11/4advisorylists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/RMIIEFINL6FUIOPD2A3M5XC6DH45Y3CCadvisorylists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/WS5RVHOIIRECG65ZBTZY7IEJVWQSQPG3refopenwall.com/lists/oss-security/2021/10/15/3refopenwall.com/lists/oss-security/2021/10/16/1reforacle.com/security-alerts/cpujan2022.htmlrefsecurity.netapp.com/advisory/ntap-20211029-0009refpacketstormsecurity.com/files/164629/Apache-2.4.49-2.4.50-Traversal-Remote-Code-Execution.htmlrefpacketstormsecurity.com/files/164941/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.htmlrefpacketstormsecurity.com/files/164501/Apache-HTTP-Server-2.4.50-Path-Traversal-Code-Execution.htmlrefpacketstormsecurity.com/files/164609/Apache-HTTP-Server-2.4.50-Remote-Code-Execution.htmlrefpacketstormsecurity.com/files/165089/Apache-HTTP-Server-2.4.50-CVE-2021-42013-Exploitation.htmlreforacle.com/security-alerts/cpuapr2022.htmlrefpacketstormsecurity.com/files/167397/Apache-2.4.50-Remote-Code-Execution.htmlrefpovilaika.com/apache-2-4-50-exploitadvisorysecurity.gentoo.org/glsa/202208-20refcisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-42013kevcisa.gov/known-exploited-vulnerabilities-catalog