CVEvulnerability
CVE-2016-4028
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2016-12-15
- Last modified
- 2026-06-17
- Assigner
- [email protected]
- CVSS 3.0 ([email protected])
- 7.5 HIGH — CVSS:3.0/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
- CVSS 2.0 ([email protected])
- 3.5 LOW — AV:N/AC:M/Au:S/C:P/I:N/A:N
- Weaknesses
- CWE-255
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.
Affected configurations
• open-xchange ox guard (<= 2.4.0)
Related
Weakness · not in database (1)
References
- http://www.securityfocus.com/archive/1/538732/100/0/threaded www.securityfocus.com
- http://www.securitytracker.com/id/1036154 Third Party Advisory, VDB Entry
- http://www.securityfocus.com/archive/1/538732/100/0/threaded www.securityfocus.com
- http://www.securitytracker.com/id/1036154 Third Party Advisory, VDB Entry