Mailing List Archive

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OSSA-2021-002: Open Redirect in noVNC proxy
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:Date: July 29, 2021
:CVE: CVE-2021-3654


Affects
~~~~~~~
- Nova: <21.2.3, >=22.0.0 <22.2.3, >=23.0.0 <23.0.2


Description
~~~~~~~~~~~
Swe Aung, Shahaan Ayyub, and Salman Khan with the Monash University
Cyber Security team reported a vulnerability affecting Nova's noVNC
proxying implementation which exposed access to a well-known
redirect behavior in the Python standard library's
http.server.SimpleHTTPRequestHandler and thus noVNC's
WebSockifyRequestHandler which uses it. By convincing a user to
follow a specially-crafted novncproxy URL, the user could be
redirected to an unrelated site under control of the attacker in an
attempt to convince them to divulge credentials or other sensitive
data. All Nova deployments with novncproxy enabled are affected.


Patches
~~~~~~~
- https://review.opendev.org/791807 (Train)
- https://review.opendev.org/791806 (Ussuri)
- https://review.opendev.org/791805 (Victoria)
- https://review.opendev.org/791577 (Wallaby)
- https://review.opendev.org/791297 (Xena)


Credits
~~~~~~~
- Swe Aung from Monash University Cyber Security team (CVE-2021-3654)
- Shahaan Ayyub from Monash University Cyber Security team (CVE-2021-3654)
- Salman Khan from Monash University Cyber Security team (CVE-2021-3654)


References
~~~~~~~~~~
- https://launchpad.net/bugs/1927677
- https://bugs.python.org/issue32084
- http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3654


Notes
~~~~~
- The stable/train branch is under extended maintenance and will
receive no new point releases, but a patch for it is provided as a
courtesy.


--
Jeremy Stanley