CVE-2026-56285

Nitter's /video media proxy endpoint fails to validate target URLs against Twitter/X domains and uses a hardcoded default HMAC key, allowing unauthenticated attackers to compute valid HMACs for arbitrary URLs. Attackers can retrieve HTTP responses from any host reachable by the server, including cloud metadata services and internal network resources.

CVSS v3 8.6 HIGH

8.6^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.0

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/zedeus/nitter/commit/44b2f096f67da2cc257a0e262a94a7ae79e95d47
https://github.com/zedeus/nitter/issues/1411
https://www.vulncheck.com/advisories/nitter-server-side-request-forgery-in-video-media-proxy-endpoint
https://github.com/zedeus/nitter/issues/1411

Configurations

No configuration.

History

25 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) El endpoint proxy de medios /video de Nitter no valida las URL de destino contra los dominios de Twitter/X y utiliza una clave HMAC predeterminada codificada, lo que permite a atacantes no autenticados calcular HMAC válidos para URL arbitrarias. Los atacantes pueden recuperar respuestas HTTP de cualquier host accesible por el servidor, incluyendo servicios de metadatos en la nube y recursos de red internos.

Information

Published : 2026-06-29 18:16

Updated : 2026-10-25 21:10

NVD link : CVE-2026-56285

Mitre link : CVE-2026-56285

CVE.ORG link : CVE-2026-56285

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

CWE-1188

Initialization of a Resource with an Insecure Default

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