PT-2026-60789 · Matrix.Org · Dendrite

George Chen · CVE-2026-63096 · Published 2026-07-17 · Updated 2026-07-17

NVD

CVSS v3.1

5.8

Medium

Base vector

AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

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.

Exploit

Fix

SSRF

Weakness Enumeration

CWE-918

Related Identifiers

CVE-2026-63096

Affected Products

Dendrite

References · 3

• 🔥 https://github.com/geo-chen/oss/blob/main/dendrite.md#finding-2-unauthenticated-ssrf-and-internal-port-scanner-via-legacy-_matrixmediar0download · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2026-63096 · Security Note
• https://vulncheck.com/advisories/dendrite-ssrf-via-unauthenticated-legacy-media-download-endpoint · Note