Headline
CVE-2023-27582: Full authentication bypass if SASL authorization username is specified
maddy is a composable, all-in-one mail server. Starting with version 0.2.0 and prior to version 0.6.3, maddy allows a full authentication bypass if SASL authorization username is specified when using the PLAIN authentication mechanisms. Instead of validating the specified username, it is accepted as is after checking the credentials for the authentication username. maddy 0.6.3 includes the fix for the bug. There are no known workarounds.
Package
gomod github.com/foxcpp/maddy (Go)
Affected versions
<=0.6.2,>=0.2.0
Description
Impact
maddy 0.2.0 - 0.6.2 allows a full authentication bypass if SASL authorization username is specified when using the PLAIN authentication mechanisms. Instead of validating the specified authorization username, it is accepted as is after checking the credentials for the authentication username.
Patches
maddy 0.6.3 includes the fix for the bug.
Workarounds
There is no way to fix the issue without upgrading.
References
- Commit that introduced the vulnerable code: 55a91a3
- Fix: 9f58cb6
Related news
### Impact maddy 0.2.0 - 0.6.2 allows a full authentication bypass if SASL authorization username is specified when using the PLAIN authentication mechanisms. Instead of validating the specified authorization username, it is accepted as is after checking the credentials for the authentication username. ### Patches maddy 0.6.3 includes the fix for the bug. ### Workarounds There is no way to fix the issue without upgrading. ### References * Commit that introduced the vulnerable code: https://github.com/foxcpp/maddy/commit/55a91a37b71210f34f98f4d327c30308fe24399a * Fix: https://github.com/foxcpp/maddy/commit/9f58cb64b39cdc01928ec463bdb198c4c2313a9c