6.9

CVE-2026-63096: matrix-org dendrite Server-Side Request Forgery (SSRF)

CVSS: 6.9v4.0MediumDeferred
Published 17-07-2026Last modified 28-07-2026
Open JSON

Vulnerability summary

CVE-2026-63096 is a medium (CVSS 6.9) Server-Side Request Forgery (SSRF) vulnerability in matrix-org dendrite. EPSS estimates a 0.34% chance of exploitation in the next 30 days, higher than 25.4% of scored vulnerabilities. 1 public exploit is recorded.

Overall risk
38/100
0100
Medium · default modelHow is this calculated?
CVSS score
6.9/10
010
Medium · v4.0 (CVE.org)
EPSS score
0.34%
0%100%
Low · 0.00 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits1github

Timeline

  1. 17-07-2026
    PublishedVulnerability first disclosed.
  2. 28-07-2026
    Last modifiedVulnerability information updated.

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.

CVSS metrics

4 scores · 2 sources · 2 versions

EPSS trend

Probability

0.34%

Chance of exploitation in the next 30 days

Percentile

25%

Versus all other CVEs

30-day change

0.00 pp

From 0.34% on 19-09-2026

19-09-202619-10-2026
EPSS score
0.34%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

1 found
  • githubUnverified

    Oss

    Maturity: poc

Weaknesses

CWE · root cause

Affected systems

Matrix-org1 product

1 vendor · 1 product

References

2 links