CVE-2026-63096 PUBLISHED

Dendrite 0.13.8 SSRF via Unauthenticated Legacy Media Download Endpoint

Assigner: VulnCheck
Reserved: 15.07.2026 Published: 17.07.2026 Updated: 17.07.2026

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.

Metrics

CVSS Vector: 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
CVSS Score: 6.9

Product Status

Vendor matrix-org
Product dendrite
Versions Default: affected
  • affected from 0 to 0.13.8 (incl.)

Credits

  • George Chen finder

References

Problem Types

  • Server-Side Request Forgery (SSRF) CWE