CVE-2026-63096

Dendrite through 0.13.8 contains a server-side request forgery vulnerability that allows unauthenticated attackers to cause the server to open outbound TLS connections to arbitrary hosts and ports by supplying an unvalidated serverName parameter to the legacy media download endpoint. Attackers can exploit distinguishable error response classes and leaked internal IP addresses in error messages to perform blind port scanning and enumerate internal network topology.

CVSS v3 5.8 MEDIUM

5.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://github.com/geo-chen/oss/blob/main/dendrite.md#finding-2-unauthenticated-ssrf-and-internal-port-scanner-via-legacy-_matrixmediar0download
https://www.vulncheck.com/advisories/dendrite-ssrf-via-unauthenticated-legacy-media-download-endpoint

Configurations

No configuration.

History

17 Jul 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-17 16:17

Updated : 2026-07-17 19:17

NVD link : CVE-2026-63096

Mitre link : CVE-2026-63096

CVE.ORG link : CVE-2026-63096

JSON object : View

Products Affected

No product.

CWE

CWE-918

Server-Side Request Forgery (SSRF)

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