CVE-2026-32255 Kan is Vulnerable to Unauthenticated SSRF via Attachment Download Endpoint
Unauthenticated attackers can exploit an SSRF vulnerability in Kan to access internal services and cloud metadata via the attachment download endpoint.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-32255?
CVE-2026-32255 is a high-severity server-side request forgery vulnerability in kanbn kan, published on 18 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.).
Weakness: CWE-918
Which versions are affected by CVE-2026-32255?
It affects 1 product.
Products include Kan Kan.
How do I fix CVE-2026-32255?
No fix has been published for CVE-2026-32255 yet. Limit exposure of the affected software until one is available.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-32255 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-32255 exists.
Public exploit code: 1 Nuclei template and 1 proofs of concept on GitHub.