Remote Yes

Type Authentication bypass

Description

A security issue was found in the Prosody.im XMPP server software before version 0.11.9. The undocumented option ‘dialback_without_dialback’ enabled an experimental feature for server-to-server authentication. A flaw in this feature meant it did not correctly authenticate remote servers, allowing a remote server to impersonate another server when this option is enabled.

AVG-1955 prosody 1:0.11.8-1 Medium Vulnerable

https://prosody.im/security/advisory_20210512/#undocumented-dialback-without-dialback-option-insecure
https://hg.prosody.im/trunk/rev/6be890ca492e
https://hg.prosody.im/trunk/rev/d0e9ffccdef9

Workaround
==========

The issue can be mitigated by removing or disabling the ‘dialback_without_dialback’ option.