Vulnerability · Published Apr 9, 2026 · Assigned by GitHub_M

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

High 7.7

In plain English

A high-severity server-side request forgery in plane from makeplane. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 17% of all known vulnerabilities).

Severity (CVSS 3.1)7.7High

Exploit odds (30 days)0.3%top 82.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

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.

Affected products (as reported)

Vendor	Product	Versions
makeplane	plane	>= 0.28.0, < 1.3.0

Weakness: CWE-918 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

References

https://github.com/makeplane/plane/security/advisories/GHSA-9fr2-pprw-pp9j x_refsource_CONFIRM