Description
Frappe Builder before 1.36.1 contains a server-side request forgery vulnerability in builder/api.py where the assert_not_private_url() guard validates only the initial hostname before callers invoke requests.get(url) with default redirect-following and no IP pinning, allowing an attacker-supplied public URL to HTTP-redirect to internal or link-local addresses the guard never validated. An authenticated attacker can call the convert_to_webp endpoint, which lacks a permission decorator, with a URL that redirects to internal targets such as cloud metadata services to perform SSRF, internal port scanning, or trigger a request-hang denial of service due to the missing timeout.
References3
Metrics
- CVSS 3.1
-
5.0
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N - CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 28 · as of 8 November 2026
- CWE
- CWE-918
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.