Arbitrary file upload in Hedgedoc

CVE-2020-26286

HedgeDoc is a collaborative platform for writing and sharing markdown. In HedgeDoc before version 1.7.1 an unauthenticated attacker can upload arbitrary files to the upload storage backend including HTML, JS and PHP files. The problem is patched in HedgeDoc 1.7.1. You should however verify that your uploaded file storage only contains files that are allowed, as uploaded files might still be served. As workaround it's possible to block the `/uploadimage` endpoint on your instance using your reverse proxy. And/or restrict MIME-types and file names served from your upload file storage.

Vulnerability class: Unrestricted File Upload

EPSS: 0.014 (70.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-26286?
CVE-2020-26286 is a high-severity vulnerability in Hedgedoc, classified under Unrestricted Upload of File with Dangerous Type. CVSS score: 7.5/10. Published 2020-12-29.
How severe is CVE-2020-26286?
High severity. CVSS v3 base score is 7.5 out of 10.