SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

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.

CRITICAL 9.2EPSS 0.41%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.41%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

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.

CVSS 4.0
9.2 CRITICALCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.41% probability · 34th percentile
CISA KEV
Not listed
Weakness
CWE-918
Source
disclosure@vulncheck.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.