Promptcraft Forge Studio's incomplete URL check is vulnerable to XSS via SVG

published 2025-09-04 14 mo ago modified 2026-06-17 4 mo ago also EUVD-2025-26851

cvss: 9.3; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.3%; EPSS 0.3% chance of exploitation in 30 days, percentile 20%
public exploits: 0; none known

Promptcraft Forge Studio is a toolkit for evaluating, optimizing, and maintaining LLM-powered applications. All versions contain an non-exhaustive URL scheme check that does not protect against XSS. User-controlled URLs pass through src/utils/validation.ts, but the check only strips `javascript:` and a few patterns. `data:` URLs (for example data:image/svg+xml,…) still pass. If a sanitized value is used in href/src, an attacker can execute a script. There is currently no fix for this issue.

CISA SSVC

Exploitation: Proof of concept is public
Automatable: no
Technical impact: total
Assessed: 14 mo ago (2025-09-04)

Exploit prediction

0.28% chance of exploitation in the next 30 days, higher than 20% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.3	CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N

Affected products

MarceloTessaro promptcraft-forge-studio

Classification

Weakness

CWE-20 Improper Input Validation
CWE-79 Improper Neutralization of Input During Web Page Generation
CWE-184 Incomplete List of Disallowed Inputs

References

github.com /MarceloTessaro/promptcraft-forge-studio/security/advisories/GHSA-fjch-4g87-g4p4

Sources

CVE List CVE-2025-58361
NVD CVE-2025-58361

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary