Medium 5.8Published Jul 17, 2026

CVE-2026-63096Dendrite 0.13.8 SSRF via Unauthenticated Legacy Media Download Endpoint

Updated under an hour ago (Oct 27, 2026, 5:23 PM ET)

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It affects matrix-org dendrite. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

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Every CVE for matrix-org dendrite

Exploited in the last 30 days

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: 5.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:N/A:N
Weakness (CWE): CWE-918
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: VulnCheck
NVD analysis: Deferred
Record last updated: Jul 27, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

matrix-org dendrite matrix_org:dendrite (from the name)	through 0.13.8	CNA record

References

References

https://github.com/geo-chen/oss/blob/main/dendrite.md#finding-2-unauthenticated-ssrf-and-internal-port-scanner-via-legacy-_matrixmediar0download	technical-description, exploit
https://www.vulncheck.com/advisories/dendrite-ssrf-via-unauthenticated-legacy-media-download-endpoint	third-party-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.