CVE-2026-32255

Kan is Vulnerable to Unauthenticated SSRF via Attachment Download Endpoint

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.).

Affected

kanbn · kan

CVSS v3.1 GITHUB

8.6 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:N

EPSS

1.74% chance of exploitation in the next 30 days, 77th percentile

Nuclei

high · CWE-918

Published

2026-03-18

Updated

2026-03-19

Proof-of-concept exploits (1)

• kOaDT/poc-cve-2026-322552★ · 2026-03-19

Nuclei templates (1)

• projectdiscovery/nuclei-templates/blob/main/http/cves/2026/CVE-2026-32255.yaml

Security advisories

• kanbn/kan/security/advisories/GHSA-qrx8-9hc6-jvqg
• kanbn/kan/commit/53397d8e81dc1494d94132848c1f0416f1152bd7

References

• CVE Record
• NVD entry

Related

• CVE-2025-29927
• CVE-2025-55182