CVE-2021-34557 — Classic Buffer Overflow in Xscreensaver

CWE-120 — Classic Buffer Overflow4 documents4 sources
Severity
4.6MEDIUMNVD
EPSS
0.1%
top 79.74%
CISA KEV
Not in KEV
Exploit
No known exploits
Affected products
4
XscreensaverDebian XscreensaverFedoraproject Fedora+1 more
Timeline
PublishedJun 10
Latest updateMay 24

Description

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.

CVSS vector

CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitability: 0.9 | Impact: 3.6

Affected Packages3 packages

▶debiandebian/xscreensaver< xscreensaver 5.45+dfsg1-2 (bookworm)
▶Debianxscreensaver/xscreensaver< 5.45+dfsg1-2+3

Also affects: Fedora 33

Patches

Patch: github.com ↗Patch: github.com ↗

🔴Vulnerability Details

2
GHSA
GHSA-hrwv-325w-f6ch: XScreenSaver 5↗2022-05-24
▶
OSV
CVE-2021-34557: XScreenSaver 5↗2021-06-10
▶

📋Vendor Advisories

1
Debian
CVE-2021-34557: xscreensaver - XScreenSaver 5.45 can be bypassed if the machine has more than ten disconnectabl...↗2021
▶
CVE-2021-34557 — Classic Buffer Overflow | cvebase