CVE-2026-32255

Kan is Vulnerable to Unauthenticated SSRF via Attachment Download Endpoint

HIGH
8.6
CVSS Score
Published: March 18, 2026 at 11:11 PM UTC
Updated: June 17, 2026 at 10:35 AM UTC
2 products affected across 2 vendorsKanKan

Using kan by kanbn?

Get instant alerts when new vulnerabilities affect kan - before attackers find them.

Real-time alertsTrack your software stackFree plan available
Severity
HIGH8.6
Exploit prediction
EPSS 26%
SSVC
No known exploit

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.).

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 0.5.5
v < 0.5.5
Affected range stops below 0.5.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

References (3)

x_refsource_CONFIRMMitigationPatchVendor Advisory
Source: cverecord
https://github.com/kanbn/kan/security/advisories/GHSA-qrx8-9hc6-jvqg
x_refsource_MISCProductRelease Notes
Source: cverecord
https://github.com/kanbn/kan/releases/tag/v0.5.5

SSVC — Action Prioritization

SSVCNo known exploitNot automatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

8.6HIGHGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusANALYZED
CWE
CWE-918

Get alerted

Stop reading CVE feeds looking for your own stack

Track the products you run and VulnTracker tells you when a new CVE affects them — with what is known about fixing it, and nothing about the rest.

Free plan, no card