In Yubico pam-u2f 1.0.7, when configured with debug and a custom debug log file is set using debug_file, that file descriptor is not closed when a new process is spawned. This leads to the file descriptor being inherited into the child process; the child process can then read from and write to it. This can leak sensitive information and also, if written to, be used to fill the disk or plant misinformation.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Pam-u2f | Yubico | 1.0.7 (including) | 1.0.7 (including) |
| Pam-u2f | Ubuntu | bionic | * |
| Pam-u2f | Ubuntu | cosmic | * |
| Pam-u2f | Ubuntu | disco | * |
| Pam-u2f | Ubuntu | trusty | * |
| Pam-u2f | Ubuntu | upstream | * |
| Pam-u2f | Ubuntu | xenial | * |
References
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00012.html
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00018.html
- http://www.openwall.com/lists/oss-security/2019/06/05/1
- https://developers.yubico.com/pam-u2f/Release_Notes.html
- https://github.com/Yubico/pam-u2f/commit/18b1914e32b74ff52000f10e97067e841e5fff62
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00012.html
- http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00018.html
- http://www.openwall.com/lists/oss-security/2019/06/05/1
- https://developers.yubico.com/pam-u2f/Release_Notes.html
- https://github.com/Yubico/pam-u2f/commit/18b1914e32b74ff52000f10e97067e841e5fff62