Firebox PPTP VPN MS-CHAPv2 information disclosure
| firebox-pptpvpn-mschapv2-info-disclosure (41683) |  Low Risk |
Description:
Firebox could allow a remote attacker to obtain sensitive information, caused by a weakness in the PPTP VPN service during MS-CHAPv2 authentication handshakes. A known error code is returned for certain authentication events. An attacker could exploit this vulnerability to enumerate user names and possibly launch further attacks against the system.
*CVSS:
| Base Score: | 5 |
| Access Vector: | Network |
| Access Complexity: | Low |
| Authentication: | None |
| Confidentiality Impact: | Partial |
| Integrity Impact: | None |
| Availability Impact: | None |
| Temporal Score: | 4.4 |
| Exploitability: | High |
| Remediation Level: | Official-Fix |
| Report Confidence: | Confirmed |
Consequences:
Obtain Information
Remedy:
Upgrade to the latest version of Firebox (10 or later), available from the WatchGuard Web site. See References.
References:
- MWR InfoSecurity Security Advisory, 4th April 2008: Watchguard Firebox PPTP VPN User Enumeration Vulnerability.
- WatchGuard Web site: WatchGuard | Powerful network protection, unified threat management, secure remote access, and expert support.
- BID-28619: WatchGuard Firebox MS-CHAPv2 Authentication Remote User Enumeration Weakness
- CVE-2008-1618: The PPTP VPN service in Watchguard Firebox before 10, when performing the MS-CHAPv2 authentication handshake, generates different error codes depending on whether the username is valid or invalid, which allows remote attackers to enumerate valid usernames.
- SA29708: WatchGuard Firebox Products User Enumeration Weakness
- SECTRACK ID: 1019796: WatchGuard Firebox PPTP VPN Discloses Whether Usernames are Valid or Invalid
- VUPEN/ADV-2008-1152: Watchguard Firebox X Remote VPN User Enumeration Weakness
Platforms Affected:
- Watchguard Firebox prior to 10
Reported:
Apr 04, 2008
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The information within this database may change without notice. Use of this information constitutes acceptance for use in an AS IS condition. There are NO warranties, implied or otherwise, with regard to this information or its use. Any use of this information is at the user's risk. In no event shall IBM be held liable for any damages whatsoever arising out of or in connection with the use or spread of this information.