National Vulnerability Database

National Vulnerability Database

National Vulnerability

CVE-2016-4028 Detail

Current Description

An issue was discovered in Open-Xchange OX Guard before 2.4.0-rev8. OX Guard uses an authentication token to identify and transfer guest users' credentials. The OX Guard API acts as a padding oracle by responding with different error codes depending on whether the provided token matches the encryption padding. In combination with AES-CBC, this allows attackers to guess the correct padding. Attackers may run brute-forcing attacks on the content of the guest authentication token and discover user credentials. For a practical attack vector, the guest users needs to have logged in, the content of the guest user's "OxReaderID" cookie and the value of the "auth" parameter needs to be known to the attacker.

Source:  MITRE
View Analysis Description


CVSS 3.x Severity and Metrics:

Base Score: 7.5 HIGH
Vector:  CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

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Hyperlink Resource Third Party Advisory VDB Entry

Weakness Enumeration

CWE-ID CWE Name Source
CWE-255 Credentials Management NIST  

Known Affected Software Configurations Switch to CPE 2.3

Configuration 1 ( hide )
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Change History

3 change records found - show changes

Quick Info

CVE Dictionary Entry:
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