What is CVE-2026-63306?

CVE-2026-63306 is a high-severity vulnerability in Stoatchat, classified under Server-Side Request Forgery (SSRF). CVSS score: 8.6/10. Published 2026-07-16.

How severe is CVE-2026-63306?

High severity. CVSS v3 base score is 8.6 out of 10.

SSRF in Stoatchat

CVE-2026-63306

stoatchat before 0.13.5 contains an unauthenticated server-side request forgery vulnerability in the /proxy and /embed endpoints that accept arbitrary URLs without DNS resolution filtering or private IP range validation. Attackers can enumerate internal services, fingerprint applications, and reach instance metadata endpoints by supplying malicious URLs or leveraging redirect chains to access internal infrastructure.

Vulnerability class: SSRF (Server-Side Request Forgery)

EPSS: 0.004 (33.9th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N.

Affected products

Stoatchat — versions 0, 0.13.5

Weakness classification (CWE)

CWE-918 — Server-Side Request Forgery (SSRF)

References

disclosure@vulncheck.com (vendor-advisory)
disclosure@vulncheck.com (third-party-advisory)

Frequently asked questions

What is CVE-2026-63306?: CVE-2026-63306 is a high-severity vulnerability in Stoatchat, classified under Server-Side Request Forgery (SSRF). CVSS score: 8.6/10. Published 2026-07-16.
How severe is CVE-2026-63306?: High severity. CVSS v3 base score is 8.6 out of 10.