CVE-2021-43856CWE-79

Stored XSS in non-image uploads in Requarks/wiki

High · published December 27, 2021

CVSS v3.1
8.2
EPSS
1%
Percentile
59.8
In the wild
Unconfirmed
What it is

Wiki.js is a wiki app built on Node.js. Wiki.js 2.5.263 and earlier is vulnerable to stored cross-site scripting through non-image file uploads for file types that can be viewed directly inline in the browser. By creating a malicious file which can execute inline JS when viewed in the browser (e.g. XML files), a malicious Wiki.js user may stage a stored cross-site scripting attack. This allows the attacker to execute malicious JavaScript when the file is viewed directly by other users. The file must be opened directly by the user and will not trigger directly in a normal Wiki.js page. A patch in version 2.5.264 fixes this vulnerability by adding an optional (enabled by default) force download flag to all non-image file types, preventing the file from being viewed inline in the browser. As a workaround, disable file upload for all non-trusted users. --- Thanks to @Haxatron for reporting this vulnerability. Initially reported via https://huntr.dev/bounties/266bff09-00d9-43ca-a4bb-bb540642811f/

The record
Technical detail
CVSS v3.1
8.2 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N
CVSS v4.0
Not supplied
EPSS
0.00916 · 59.8th percentile
Weakness
CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Published
2021-12-27T18:05Z
EPSS history
Timeline
  • 27 DEC 18:05Z
    Stored XSS in non-image uploads in Requarks/wiki
    cvelistv5