CVE-2026-39843 HIGH

CVE-2026-39843: Plane has a Server-Side Request Forgery (SSRF) in Favicon Fetching

Vendor Makeplane
Product plane
Weakness CWE-918 · SSRF
Published April 9, 2026
Last update April 13, 2026

CVSS base score

7.7/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity None

CVSS vector

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

What the vulnerability does

01Description

Plane is an an open-source project management tool. From 0.28.0 to before 1.3.0, the remediation of GHSA-jcc6-f9v6-f7jw is incomplete which could lead to the same full read Server-Side Request Forgery when a normal html page contains a link tag with an href that redirects to a private IP address is supplied to Add link by an authenticated attacker with low privileges. Redirects for the main page URL are validated, but not the favicon fetch path. fetch_and_encode_favicon() still uses requests.get(favicon_url, ...) with the default redirect-following. This vulnerability is fixed in 1.3.0.

Key dates

02Disclosure timeline

April 9, 2026 CVE published
April 13, 2026 Record updated