Vulnerability · Published Jan 22, 2021 · Assigned by GitHub_M
CVE-2021-21259Stored XSS in slide mode
High 7.4
In plain English
A high-severity cross-site scripting in hedgedoc from hedgedoc. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.4% (higher than 72% of all known vulnerabilities).
Official description
HedgeDoc is open source software which lets you create real-time collaborative markdown notes. In HedgeDoc before version 1.7.2, an attacker can inject arbitrary JavaScript into a HedgeDoc note, which is executed when the note is viewed in slide mode. Depending on the configuration of the instance, the attacker may not need authentication to create or edit notes. The problem is patched in HedgeDoc 1.7.2. As a workaround, disallow loading JavaScript from 3rd party sites using the `Content-Security-Policy` header. Note that this will break some embedded content.
Affected products (as reported)
Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N
References
- https://github.com/hedgedoc/hedgedoc/security/advisories/GHSA-44w9-vm8p-3cxw x_refsource_CONFIRM
- https://github.com/hedgedoc/hedgedoc/releases/tag/1.7.2 x_refsource_MISC
- https://github.com/hedgedoc/hedgedoc/commit/35b0d39a12aa35f27fba8c1f50b1886706e7efef x_refsource_MISC
- https://github.com/hackmdio/codimd/issues/1648 x_refsource_MISC