Description
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.
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | pam-u2f | 1.0.8-1 | — |
| Debian 13 | pam-u2f | 1.0.8-1 | — |
| Debian 12 | pam-u2f | 1.0.8-1 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP1 | libu2f-host | 1.1.6-3.6.1 | SUSE-SU-2019:1750-1 |
| SLES 15 SP1 | pam_u2f | 1.0.8-3.3.1 | SUSE-SU-2019:1750-1 |
| SLES 15 | libu2f-host | 1.1.6-3.6.1 | SUSE-SU-2019:1750-1 |
| SLES 15 | pam_u2f | 1.0.8-3.3.1 | SUSE-SU-2019:1750-1 |
| SLES 12 SP4 | libu2f-host | 1.1.6-3.5.1 | SUSE-SU-2019:1749-1 |
| SLES 12 SP4 | pam_u2f | 1.0.8-3.3.1 | SUSE-SU-2019:1749-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP4 | libu2f-host | 1.1.6-3.5.1 | SUSE-SU-2019:1749-1 |
| SLES for SAP 12 SP4 | pam_u2f | 1.0.8-3.3.1 | SUSE-SU-2019:1749-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | pam_u2f | 1.1.1-1.3 | openSUSE-SU-2024:11145-1 |
| openSUSE Leap 15.1 | libu2f-host | 1.1.6-lp151.2.6.1 | openSUSE-SU-2019:1708-1 |
| openSUSE Leap 15.1 | pam_u2f | 1.0.8-lp151.2.3.1 | openSUSE-SU-2019:1708-1 |
| openSUSE Leap 15.0 | libu2f-host | 1.1.6-lp150.10.1 | openSUSE-SU-2019:1725-1 |
| openSUSE Leap 15.0 | pam_u2f | 1.0.8-lp150.7.1 | openSUSE-SU-2019:1725-1 |
Advisories 5
- SUSE-SU-2019:1749-1 Security update for libu2f-host SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:1750-1 Security update for libu2f-host, pam_u2f SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11145-1 pam_u2f-1.1.1-1.3 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:1708-1 Security update for libu2f-host, pam_u2f SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2019:1725-1 Security update for libu2f-host, pam_u2f SUSE / openSUSE Security Updates · Feb 4, 2026
References
- https://developers.yubico.com/pam-u2f/Release_Notes.html
- https://github.com/Yubico/pam-u2f/commit/18b1914e32b74ff52000f10e97067e841e5fff62
- [oss-security] 20190605 pam-u2f: CVE-2019-12210: debug_file file descriptor leak, CVE-2019-12209: symlink attack on u2f_keys leading to possible information leak mailing-list
- openSUSE-SU-2019:1708 vendor-advisory
- openSUSE-SU-2019:1725 vendor-advisory