// For flags

CVE-2016-4028

 

Severity Score

7.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

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.

Se descubrió un problema en OX Guard de Open-Xchange anterior a versión 2.4.0-rev8. OX Guard utiliza un token de autenticación para identificar y transferir las credenciales de usuarios invitados. La API de OX Guard actúa como un oráculo de relleno (padding oracle) al responder con diferentes códigos de error dependiendo de si el token provisto coincide con el cifrado de relleno (encryption padding). En combinación con AES-CBC, esto permite a los atacantes adivinar el relleno correcto. Los atacantes pueden ejecutar ataques violentos en el contenido del token de autenticación del invitado y detectar las credenciales del usuario. Para un vector de ataque práctico, los usuarios invitados necesitan haber iniciado sesión, el contenido de la cookie "OxReaderID" del usuario invitado y el valor del parámetro "auth" deben ser conocidos por el atacante.

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
High
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
Attack Vector
Network
Attack Complexity
Medium
Authentication
Single
Confidentiality
Partial
Integrity
None
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2016-04-15 CVE Reserved
  • 2016-12-15 CVE Published
  • 2023-03-08 EPSS Updated
  • 2024-08-06 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-255: Credentials Management Errors
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Open-xchange
Search vendor "Open-xchange"
 Ox Guard
Search vendor "Open-xchange" for product "Ox Guard"
 <= 2.4.0
Search vendor "Open-xchange" for product "Ox Guard" and version " <= 2.4.0"
rev7
Affected