CVE-2026-63096 | Dendrite through 0.13.8 contains a server-side request forge… | CVSS 5.8 MEDIUM

Description

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.

Metadata

CVE ID: CVE-2026-63096
State: PUBLISHED
Assigner: VulnCheck
Reserved: 2026-07-15 15:45 UTC
Published: 2026-07-17 15:30 UTC
Last updated: 2026-07-17 15:30 UTC
Primary CWE: CWE-918
Server-Side Request Forgery (SSRF)
Vendor / Product: matrix-org / dendrite
Sources: cve.org · NVD

Severity & Metrics

5.8 MEDIUM CVSS 3.1

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

Affected products (1)

Vendor	Product	Platform	Versions
matrix-org	dendrite	—	0 ≤ 0.13.8

Weakness (CWE)

CWE	Source	Description
CWE-918	cna	Server-Side Request Forgery (SSRF)

CVSS scores (2)

Score	Severity	Version	Source	Vector
6.9	MEDIUM	4.0	cna	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
5.8	MEDIUM	3.1	cna	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N

References (2)