Description
Anubis is a Web AI Firewall Utility that weighs the soul of users' connections using one or more challenges in order to protect upstream resources from scraper bots. In versions 1.21.2 and below, attackers can craft malicious pass-challenge pages that cause a user to execute arbitrary JavaScript code or trigger other nonstandard schemes. An incomplete version of this fix was tagged at 1.21.2 and then the release process was aborted upon final testing. To work around this issue: block any requests to the /.within.website/x/cmd/anubis/api/pass-challenge route with the ?redir= parameter set to anything that doesn't start with the URL scheme http, https, or no scheme (local path redirect). This was fixed in version 1.21.3.
Scores
CVSS v4
5.1
EPSS
0.0007
EPSS Percentile
21.3%
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-601
CWE-80
Status
published
Products (1)
TecharoHQ/anubis
< 1.21.3
Published
Jul 26, 2025
Tracked Since
Feb 18, 2026