Vigil@nce: Citrix Online Plug-in, ICA Client, spoofing of X.509 certificate
November 2009 by Vigil@nce
An attacker can setup a server with a malicious X.509 certificate,
in order to deceive victims connecting with Citrix Online Plug-in
or an ICA Client.
Severity: 2/4
Consequences: user access/rights, data reading, data
creation/edition
Provenance: internet server
Means of attack: no proof of concept, no attack
Ability of attacker: expert (4/4)
Confidence: confirmed by the editor (5/5)
Diffusion of the vulnerable configuration: high (3/3)
Creation date: 12/11/2009
IMPACTED PRODUCTS
– Citrix XenApp
– Citrix XenDesktop
DESCRIPTION OF THE VULNERABILITY
The Citrix Online Plug-in (ICA Client) products are used to
connect to XenApp and XenDesktop. The ICA (Independent Computing
Architecture) stream can be secured via a SSL/TLS session.
However, clients do not check if the X.509 certificate offered by
the server is valid, before accepting the session.
An attacker can therefore setup a server with a malicious X.509
certificate, in order to deceive victims connecting with Citrix
Online Plug-in or an ICA Client.
This vulnerability seems to be similar to VIGILANCE-VUL-8908
(https://vigilance.fr/tree/1/8908), but this is unconfirmed.
CHARACTERISTICS
Identifiers: VIGILANCE-VUL-9192