// For flags

CVE-2021-29431

SSRF in Sydent due to missing validation of hostnames

Severity Score

6.5
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

Sydent is a reference Matrix identity server. Sydent can be induced to send HTTP GET requests to internal systems, due to lack of parameter validation or IP address blacklisting. It is not possible to exfiltrate data or control request headers, but it might be possible to use the attack to perform an internal port enumeration. This issue has been addressed in in 9e57334, 8936925, 3d531ed, 0f00412. A potential workaround would be to use a firewall to ensure that Sydent cannot reach internal HTTP resources.

Sydent es un servidor de identidad Matrix de referencia. Sydent puede ser inducido a enviar peticiones HTTP GET hacia sistemas internos, debido a una falta de comprobación de parámetros o la lista negra de direcciones IP. No es posible exfiltrar datos o controlar los encabezados de peticiones, pero podría ser posible utilizar el ataque para llevar a cabo una enumeración de puertos internos. Este problema ha sido abordado en 9e57334, 8936925, 3d531ed, 0f00412. Una posible solución alternativa sería utilizar un firewall para garantizar que Sydent no pueda acceder a los recursos HTTP internos

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
None
Availability
None
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Changed
Confidentiality
High
Integrity
None
Availability
None
Attack Vector
Network
Attack Complexity
Low
Authentication
Single
Confidentiality
Partial
Integrity
None
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-03-30 CVE Reserved
  • 2021-04-15 CVE Published
  • 2024-08-03 CVE Updated
  • 2024-12-17 EPSS Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-20: Improper Input Validation
  • CWE-918: Server-Side Request Forgery (SSRF)
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Matrix
Search vendor "Matrix"
Sydent
Search vendor "Matrix" for product "Sydent"
< 2.3.0
Search vendor "Matrix" for product "Sydent" and version " < 2.3.0"
-
Affected