Cyber Resilience

CVE-2021-26937

CriticalPublic PoC

Published: 09 February 2021

Published
09 February 2021
Modified
09 May 2025
KEV Added
Patch
CVSS Score v3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.1265 94.1th percentile
Risk Priority 27 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-26937 is a critical-severity Argument Injection (CWE-88) vulnerability in Debian Debian Linux. Its CVSS base score is 9.8 (Critical).

Operationally, ranked in the top 5.9% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

encoding.c in GNU Screen through 4.8.0 allows remote attackers to cause a denial of service (invalid write access and application crash) or possibly have unspecified other impact via a crafted UTF-8 character sequence.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

gnu
screen
≤ 4.8.0
debian
debian linux
10.0, 9.0
fedoraproject
fedora
32, 33

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References