medium4.6
CVE-2021-34557
XScreenSaver 5.45 can be bypassed if the machine has more than ten disconnectable video outputs.
Impact
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.
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Xscreensaver Project | Xscreensaver | Version 5.45 |
| Fedoraproject | Fedora | Version 33 |
Weakness classification
References
- NVD record
- CVE.org record
- http://www.openwall.com/lists/oss-security/2021/06/11/1
- http://www.openwall.com/lists/oss-security/2021/07/06/2
- https://github.com/QubesOS/qubes-issues/issues/6595
- https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-068-2021.txt
- https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TC4QB7TRS4GS7LDXQQ4PC6J3LVFJYISV/
- https://www.openwall.com/lists/oss-security/2021/06/05/1
- http://www.openwall.com/lists/oss-security/2021/06/11/1
- http://www.openwall.com/lists/oss-security/2021/07/06/2
- https://github.com/QubesOS/qubes-issues/issues/6595
- https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-068-2021.txt
- https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TC4QB7TRS4GS7LDXQQ4PC6J3LVFJYISV/
- https://www.openwall.com/lists/oss-security/2021/06/05/1