Vulnerabilities 2010

PR10-06 Cross-domain redirect on PGP Universal Web Messenger

• Advisory publicly released: Thursday, 16 December 2010
• Vulnerability found: Wednesday, 10 February 2010
• Vendor informed: Wednesday, 10 February 2010
• Vulnerability fixed: Tuesday, 14 December 2010
• Severity level: Medium/High

• Credits
  Jan Fry of ProCheckUp Ltd (www.procheckup.com).
• Description
  A remote URI redirection vulnerability affects the PGP Universal Web Messenger. This issue is due to a failure of the application to properly sanitize URI-supplied data assigned to the 'retryURL' parameter.
  
  An attacker may leverage this issue to carry out convincing phishing attacks against unsuspecting users by causing an arbitrary page to be loaded once a PGP Universal Web Messenger specially-crafted URL is visited.
  
  Vulnerable server-side script: '/b/lnj.e?'
  
  Unfiltered parameter: 'retryURL'
• Proof of concept
  Example of specially-crafted URL:
  
  https://target-domain.foo/b/lnj.e?retryURL=//www.procheckup.com
  
  Consequences:
  
  Victim users can be redirected to third-party sites for the purpose of exploiting browser vulnerabilities or performing phishing attacks.
• How to fix
  The vendor has stated that this issue was addressed in the PGP Universal Web Messenger.
• References
  
  
• Legal
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