CVE-2026-39843: Plane is an an open-source project management tool. From 0.28.0 to before 1.3.0, the remediation of…
CVE-2026-39843 · Severity: high · CVSS 7.7 · Published 2026-04-09
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.
No. Junglewise Threat Intelligence has no report of CVE-2026-39843 being exploited in the wild.
How severe is CVE-2026-39843?
High severity, with a CVSS score of 7.7, published 9 April 2026.
Which products and versions are affected?
Plane. The advisory does not name versions.
Is there a fix for CVE-2026-39843?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
Am I affected by CVE-2026-39843?
Check whether you run Plane. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.