CVE-2021-34557

CVSS V2 Low 2.1 CVSS V3 Medium 4.6
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.
Overview
  • CVE ID
  • CVE-2021-34557
  • Assigner
  • cve@mitre.org
  • Vulnerability Status
  • Analyzed
  • Published Version
  • 2021-06-10T16:15:08
  • Last Modified Date
  • 2021-09-21T16:39:09
Weakness Enumerations
CWE URL
CWE-120 http://cwe.mitre.org/data/definitions/120.html
CPE Configuration (Product)
CPE Vulnerable Operator Version Start Version End
cpe:2.3:a:xscreensaver_project:xscreensaver:5.45:*:*:*:*:*:*:* 1 OR
cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:* 1 OR
CVSS Version 2
  • Version
  • 2.0
  • Vector String
  • AV:L/AC:L/Au:N/C:N/I:N/A:P
  • Access Vector
  • LOCAL
  • Access Compatibility
  • LOW
  • Authentication
  • NONE
  • Confidentiality Impact
  • NONE
  • Integrity Impact
  • NONE
  • Availability Impact
  • PARTIAL
  • Base Score
  • 2.1
  • Severity
  • LOW
  • Exploitability Score
  • 3.9
  • Impact Score
  • 2.9
CVSS Version 3
  • Version
  • 3.1
  • Vector String
  • CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
  • Attack Vector
  • PHYSICAL
  • Attack Compatibility
  • LOW
  • Privileges Required
  • NONE
  • User Interaction
  • NONE
  • Scope
  • UNCHANGED
  • Confidentiality Impact
  • NONE
  • Availability Impact
  • HIGH
  • Base Score
  • 4.6
  • Base Severity
  • MEDIUM
  • Exploitability Score
  • 0.9
  • Impact Score
  • 3.6
References
Reference URL Reference Tags
https://github.com/QubesOS/qubes-xscreensaver/blob/master/0001-Fix-updating-outputs-info.patch Patch Third Party Advisory
https://github.com/QubesOS/qubes-issues/issues/6595 Issue Tracking Third Party Advisory
https://github.com/QubesOS/qubes-secpack/blob/master/QSBs/qsb-068-2021.txt Exploit Third Party Advisory
https://www.openwall.com/lists/oss-security/2021/06/05/1 Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/06/11/1 Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/07/06/2 Exploit Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TC4QB7TRS4GS7LDXQQ4PC6J3LVFJYISV/ Mailing List Third Party Advisory
Sources
Source Name Source URL
NIST https://nvd.nist.gov/vuln/detail/CVE-2021-34557
MITRE https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-34557
History
Created Old Value New Value Data Type Notes
2022-05-10 06:54:20 Added to TrackCVE
2022-12-05 04:09:51 2021-06-10T16:15Z 2021-06-10T16:15:08 CVE Published Date updated
2022-12-05 04:09:51 2021-09-21T16:39:09 CVE Modified Date updated
2022-12-05 04:09:51 Analyzed Vulnerability Status updated