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TI-2026-24784 Aliases CVE-2026-32255

Kan is Vulnerable to Unauthenticated SSRF via Attachment Download Endpoint

Priority MEDIUM 59CWE-918Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
High · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-918 and the CVSS impact.

Summary

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.).

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.26901 98th percentileScored 2026-11-07
Fix Fixed kan (kanbn): 0.5.5

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
kanbnkanbefore 0.5.50.5.5Patch availableCNA
  • kan Vendorkanbn Affected before 0.5.5 Fixed in 0.5.5 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:kan:kan:*:*:*:*:*:*:*:*before 0.5.5VulnerableKan
  • cpe:2.3:a:kan:kan:*:*:*:*:*:*:*:* Versions before 0.5.5 Vulnerable ·Kan

Remediation

  • Fix · CNA kan (kanbn) Fixed in 0.5.5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-32255
  2. 2026-10-25 EPSS moved to the 95th–99th percentile

References

Patch 2

Other 1

  • TI-2026-74122 Unauthenticated server-side request forgery in Kan download route CVSS 4.0CRITICAL 9.2
  • TI-2026-62541 kan through 0.6.0 Authorization Bypass via GitHub Project Import CVSS 4.0MEDIUM 5.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences