Vulnerability · Published Dec 20, 2021 · Assigned by GitHub_M

CVE-2021-43842Stored XSS via SVG file upload in Wiki.js

Medium 5.4

In plain English

A medium-severity cross-site scripting in wiki from Requarks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.7% (higher than 55% of all known vulnerabilities).

Severity (CVSS 3.1)5.4Medium

Exploit odds (30 days)0.7%top 45.1% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official description

Wiki.js is a wiki app built on Node.js. Wiki.js versions 2.5.257 and earlier are vulnerable to stored cross-site scripting through a SVG file upload. By creating a crafted SVG file, a malicious Wiki.js user may stage a stored cross-site scripting attack. This allows the attacker to execute malicious JavaScript when the SVG is viewed directly by other users. Scripts do not execute when loaded inside a page via normal `<img>` tags. Commit 5d3e81496fba1f0fbd64eeb855f30f69a9040718 fixes this vulnerability by adding an optional (enabled by default) SVG sanitization step to all file uploads that match the SVG mime type. As a workaround, disable file upload for all non-trusted users. Wiki.js version 2.5.260 is the first production version to contain a patch. Version 2.5.258 is the first development build to contain a patch and is available only as a Docker image as requarks/wiki:canary-2.5.258.

Affected products (as reported)

Vendor	Product	Versions
Requarks	wiki	< 2.5.258 (development)< 2.5.260 (production)

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N

References

https://github.com/Requarks/wiki/security/advisories/GHSA-3qv4-gp35-rgh7 x_refsource_CONFIRM
https://github.com/Requarks/wiki/commit/5d3e81496fba1f0fbd64eeb855f30f69a9040718 x_refsource_MISC
https://github.com/Requarks/wiki/releases/tag/2.5.260 x_refsource_MISC