Is It On KEV?

Sudo Sudo

YES - ON THE CISA KEV LIST
CVE-2021-3156

Sudo Heap-Based Buffer Overflow Vulnerability

CISA catalog due date2022-04-27
overdue since 2022-04-27
EPSS exploit probability (next 30 days)100.0% · 100percentile
From CVE publication to KEV listing435 days (2021-01-26 → 2022-04-06)
Remediation window (KEV listing to due date)21 days
Days on the KEV list1680 days
Date added to KEV2022-04-06
Known ransomware campaign useUnknown
VendorSudo
ProductSudo
Weaknesses (CWE)CWE-122, CWE-193

Sudo: 2 entries (0.1% of all KEV entries are from this vendor); 0 added in 2026.

BOD 26-04 note: this is the date printed in the CISA catalog. A federal agency's actual deadline is set by its SSVC tier - Act (3 days), Attend (14 days), Track (60 days), or the next scheduled upgrade - counted from the KEV listing date or the date the vulnerability is identified in its environment, whichever comes first. Use the tier helper on each CVE page for your own window.

Your BOD 26-04 window (SSVC tier helper)

Your remediation window ends:

Description

Sudo contains an off-by-one error that can result in a heap-based buffer overflow, which allows for privilege escalation.

Required action (CISA)

Apply updates per vendor instructions.

Notes

https://nvd.nist.gov/vuln/detail/CVE-2021-3156

References

Other KEV entries for this vendor: Sudo

Sudo - Vendors with KEV entries

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