Kan is an open-source project management tool. In versions 0.5.4 and below, the /api/download/attatchment endpoint has no authentication and no URL validation. The Attachment Download endpoint accepts a user-supplied URL query parameter and passes it directly to fetch() server-side, and returns the full response body. An unauthenticated attacker can use this to make HTTP requests from the server to internal services, cloud metadata endpoints, or private network resources. This issue has been fixed in version 0.5.5. To workaround this issue, block or restrict access to /api/download/attatchment at the reverse proxy level (nginx, Cloudflare, etc.).
Conclusion & alert: CVE-2026-32255 is rated Moderate Risk (40.3/100): CVSS High severity, with low exploitation likelihood (EPSS 0.05%). Mandatory action: Review affected assets and schedule remediation.
Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.
EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).
| # | Date | Old EPSS score | New EPSS score | Delta (New - Old) |
|---|---|---|---|---|
| 1 | 2026-03-24 | 0.04% | 0.05% | +0.01% |
| 2 | 2026-03-22 | 0.09% | 0.04% | -0.04% |
| 3 | 2026-03-19 | — | 0.09% | — |
Full EPSS history (3 records total)
CVSS metrics for this CVE.
| Base score | Version | Severity | Vector | Exploitability | Impact | Score source |
|---|---|---|---|---|---|---|
| 8.6 | 3.1 | HIGH |
|
3.9 | 4.0 | [email protected] |
| URL | Tags |
|---|---|
| https://github.com/kanbn/kan/commit/53397d8e81dc1494d94132848c1f0416f1152bd7 | Patch |
| https://github.com/kanbn/kan/releases/tag/v0.5.5 | Product Release Notes |
| https://github.com/kanbn/kan/security/advisories/GHSA-qrx8-9hc6-jvqg | Mitigation Patch Vendor Advisory |