A vulnerability was discovered in gdm before 3.31.4. When timed login is enabled in configuration, an attacker could bypass the lock screen by selecting the timed login user and waiting for the timer to expire, at which time they would gain access to the logged-in user's session.
The MITRE CVE dictionary describes this issue as:
Find out more about CVE-2019-3825 from the MITRE CVE dictionary dictionary and NIST NVD.
NOTE: The following CVSS v3 metrics and score provided are preliminary and subject to review.
| CVSS3 Base Score | 6.3 |
|---|---|
| CVSS3 Base Metrics | CVSS:3.0/AV:P/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H |
| Attack Vector | Physical |
| Attack Complexity | High |
| Privileges Required | None |
| User Interaction | Required |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity Impact | High |
| Availability Impact | High |
| Platform | Package | State |
|---|---|---|
| Red Hat Enterprise Linux 7 | gdm | Affected |
| Red Hat Enterprise Linux 6 | gdm | Will not fix |
Ensure timed login is not enabled in gdm configuration, by checking the output of:
grep TimedLogin /etc/gdm/custom.conf
Vulmon