CVE-2021-34557: 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…

PriorityP418medium4.6CVSS 3.1

AVPACLPRNUINSUCNINAH

EPSS

0.48%

38.3th percentile

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

7 ranges

Vendor	Product	Version range	Fixed in
debian	xscreensaver	< xscreensaver 5.45+dfsg1-2 (bookworm)	xscreensaver 5.45+dfsg1-2 (bookworm)
fedoraproject	fedora	—	—
xscreensaver	xscreensaver	>= 0 < 5.45+dfsg1-2	5.45+dfsg1-2
xscreensaver	xscreensaver	>= 0 < 5.45+dfsg1-2	5.45+dfsg1-2
xscreensaver	xscreensaver	>= 0 < 5.45+dfsg1-2	5.45+dfsg1-2
xscreensaver	xscreensaver	>= 0 < 5.45+dfsg1-2	5.45+dfsg1-2
xscreensaver_project	xscreensaver	—	—

CVSS provenance

nvdv3.14.6MEDIUMCVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.02.1LOWAV:L/AC:L/Au:N/C:N/I:N/A:P

osv4.6MEDIUM

vendor_debian4.6MEDIUM

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