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By Date By Thread Executable installers are vulnerable^WEVIL (case 19): ZoneAlarm's installers allow arbitrary (remote) code execution and escalation of privilege From: "Stefan Kanthak" <stefan.kanthak () nexgo de>

Date: Thu, 7 Jan 2016 11:45:35 +0100

Hi @ll, the executable installers ZASPSetupWeb_141_011_000.exe and zafwSetupWeb_141_011_000.exe load and execute (at least) UXTheme.dll, WindowsCodecs.dll and ProfAPI.dll from their "application directory". For software downloaded with a web browser the application directory is typically the user's "Downloads" directory: see <https://insights.sei.cmu.edu/cert/2008/09/carpet-bombing-and-directory-poisoning.html>, <http://blog.acrossecurity.com/2012/02/downloads-folder-binary-planting.html> and <http://seclists.org/fulldisclosure/2012/Aug/134> for "prior art" about this well-known and well-documented vulnerability. If an attacker places the above named DLLs in the users "Downloads" directory (for example per drive-by download or social engineering) this vulnerability becomes a remote code execution. Due to the application manifest embedded in the executables which specifies "requireAdministrator" the executable installers are run with administrative privileges ("protected" administrators are prompted for consent, unprivileged standard users are prompted for an administrator password); execution of the DLLs therefore results in an escalation of privilege! Proof of concept (verified on Windows XP, Windows Vista, Windows 7, Windows Server 2008 [R2]; should work on newer versions too): 1. visit <http://home.arcor.de/skanthak/sentinel.html>, download <http://home.arcor.de/skanthak/download/SENTINEL.DLL> and save it as UXTheme.dll in your "Downloads" directory, then copy it as ProfAPI.dll and WindowsCodecs.dll; 2. download ZASPSetupWeb_141_011_000.exe and/or zafwSetupWeb_141_011_000.exe and save them in your "Downloads" directory; 3. run ZASPSetupWeb_141_011_000.exe and/or zafwSetupWeb_141_011_000.exe from the "Downloads" directory. PWNED! From the vendor's web site <http://www.zonealarm.com/security/en-us/fza-install-steps.htm> | To start installation: | * Click Save File on the browser pop up. ... | * By default your downloaded file will be in the Downloads | folder under Documents. Double-click the zafwSetupWeb.exe | file to begin installation. OUCH! For this well-known (trivial, easy to avoid, easy to detect and easy to fix) beginner's error see <https://capec.mitre.org/data/definitions/471.html>, <https://technet.microsoft.com/en-us/library/2269637.aspx>, <https://msdn.microsoft.com/en-us/library/ff919712.aspx> and <https://msdn.microsoft.com/en-us/library/ms682586.aspx> plus <http://blogs.technet.com/b/srd/archive/2014/05/13/load-library-safely.aspx> Additionally: ZASPSetupWeb_141_011_000.exe and zafwSetupWeb_141_011_000.exe create the UNSAFE temporary directory %TEMP%\{907A1104-E812-4b5c-959B-E4DAB37A96AB} to unpack their payload and download other executables, including your real executable installer install.exe, which has but the same bugs! Proof of concept (verified on Windows XP, Windows Vista, Windows 7, Windows Server 2008 [R2]; should work on newer versions too): 4. create the directory %TEMP%\{907A1104-E812-4b5c-959B-E4DAB37A96AB}; 5. copy UXTheme.dll and WindowsCodecs.dll downloaded in step 1 above into this empty directory; for a denial of service copy it as PowrProf.dll, WebIO.dll, WinHttp.dll, Version.dll and MSWSock.dll (or create your own DLL which exports the referenced entries to have them loaded and executed too); 6. run ZASPSetupWeb_141_011_000.exe and/or zafwSetupWeb_141_011_000.exe from step 3 above. PWNED! resp. DOSSED! For this well-known (trivial, easy to avoid, easy to detect and easy to fix) beginner's error see <https://cwe.mitre.org/data/definitions/377.html>, <https://cwe.mitre.org/data/definitions/379.html>, <https://capec.mitre.org/data/definitions/27.html>, <https://capec.mitre.org/data/definitions/29.html> ... See <http://seclists.org/fulldisclosure/2015/Nov/101>, <http://seclists.org/fulldisclosure/2015/Dec/86> and <http://seclists.org/fulldisclosure/2015/Dec/121> plus <http://home.arcor.de/skanthak/sentinel.html> and the still unfinished <http://home.arcor.de/skanthak/!execute.html> for more details and why executable installers (and self-extractors too) are bad and should be dumped. stay tuned Stefan Kanthak PS: I really LOVE (security) software with such trivial beginner's errors. It's a tell-tale sign to stay away from this crapware! Timeline: ~~~~~~~~~ 2015-12-13 report sent to vendor NO ANSWER, not even an acknowledgement of receipt 2015-12-23 reports resent to vendor NO ANSWER, not even an acknowledgement of receipt 2016-01-01 reports resent to vendor NO ANSWER, not even an acknowledgement of receipt 2016-01-07 report published _______________________________________________ Sent through the Full Disclosure mailing list https://nmap.org/mailman/listinfo/fulldisclosure Web Archives & RSS: http://seclists.org/fulldisclosure/ By Date By Thread Current thread: Executable installers are vulnerable^WEVIL (case 19): ZoneAlarm's installers allow arbitrary (remote) code execution and escalation of privilege Stefan Kanthak (Jan 08)