CVE-2026-63096mediumCWE-918

CVE-2026-63096: medium-severity vulnerability in matrix-org dendrite

Dendrite 0.13.8 SSRF via Unauthenticated Legacy Media Download Endpoint

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33Vexday Risk Score

No sign of exploitation. It has a public proof of concept.

ssvc Attendcvss 6.9epss 0.3%
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:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N
Affected products
matrix-org · dendrite
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