Legcord 1.1.0 through 1.3.0 contains a configuration injection vulnerability that allows script in the Discord page to write any config key via the window.legcord settings.setConfig bridge. Attackers exploiting a Discord XSS can set additionalArguments to persistently add --proxy-server and --ignore-certificate-errors switches, routing all client traffic through an interception proxy.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
High
Difficult to exploit
Attack Requirements
Present
Additional conditions required
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
High
Complete data leak
Integrity
High
Complete data modification
Availability
None
No disruption
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products
legcord:legcord
References 5
https://github.com/Legcord/Legcord
disclosure@vulncheck.com
https://github.com/Legcord/Legcord/blob/v1.3.0/src/discord/ipc.ts#L296-L299
disclosure@vulncheck.com
https://github.com/Legcord/Legcord/blob/v1.3.0/src/main.ts#L277-L307
disclosure@vulncheck.com
https://github.com/Legcord/Legcord/issues/1163
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/legcord-1.1.0-through-1.3.0-chromium-switc…
disclosure@vulncheck.com