CVE-2021-34557
Publication date 10 June 2021
Last updated 24 July 2024
Ubuntu priority
Cvss 3 Severity Score
XScreenSaver 5.45 can be bypassed if the machine has more than ten disconnectable video outputs. A buffer overflow in update_screen_layout() allows an attacker to bypass the standard screen lock authentication mechanism by crashing XScreenSaver. The attacker must physically disconnect many video outputs.
Status
Package | Ubuntu Release | Status |
---|---|---|
xscreensaver | 24.10 oracular |
Not affected
|
24.04 LTS noble |
Not affected
|
|
22.04 LTS jammy |
Needs evaluation
|
|
20.04 LTS focal |
Needs evaluation
|
|
18.04 LTS bionic |
Needs evaluation
|
|
16.04 LTS xenial |
Needs evaluation
|
|
14.04 LTS trusty | Not in release |
Severity score breakdown
Parameter | Value |
---|---|
Base score | 4.6 · Medium |
Attack vector | Physical |
Attack complexity | Low |
Privileges required | None |
User interaction | None |
Scope | Unchanged |
Confidentiality | None |
Integrity impact | None |
Availability impact | High |
Vector | CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References
Other references
- https://www.openwall.com/lists/oss-security/2021/06/05/1
- https://www.openwall.com/lists/oss-security/2021/06/05/2
- https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch
- https://github.com/QubesOS/qubes-issues/issues/6595
- https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-068-2021.txt
- https://www.cve.org/CVERecord?id=CVE-2021-34557