The Logfile feature in Yahoo! Messenger 5.x through 6.0 can be activated by a YMSGR: URL and writes all output to a single ypager.log file, even when there are multiple users, and does not properly warn later users that the feature has been enabled, which allows local users to obtain sensitive information from other users.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Messenger | Yahoo | 5.5 (including) | 5.5 (including) |
| Messenger | Yahoo | 5.6 (including) | 5.6 (including) |
| Messenger | Yahoo | 5.6.0.1351 (including) | 5.6.0.1351 (including) |
| Messenger | Yahoo | 6.0 (including) | 6.0 (including) |