CVE-2021-34557
Published: 10 June 2021
Summary
CVE-2021-34557 is a medium-severity Classic Buffer Overflow (CWE-120) vulnerability in Xscreensaver Project Xscreensaver. Its CVSS base score is 4.6 (Medium).
Operationally, ranked at the 38.5th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-21207
Vulnerability details
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…
more
video outputs.
- CWE(s)
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Likely Mitigating Controls AI
Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.
Platform-independent managed code eliminates the need for unchecked native buffer copies that are the root cause of classic buffer overflows.