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CVE-2021-3156: Sudo Heap-Based Buffer Overflow Vulnerability
Sudo Sudo · in CISA KEV since 2022-04-06
2022-04-06added to KEV
2022-04-27federal remediation due date
99.97%EPSS exploit probability (30 days) 100.0th percentile
7.8 HIGHCVSS 3.1
Unknownknown ransomware use
435days from NVD publication to KEV
What it is
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.
| CWE | CWE-122;CWE-193 |
|---|---|
| CVSS vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
| NVD published | 2021-01-26 (Analyzed) |
Original records: NVD · CISA KEV · JSON: /api/cve/CVE-2021-3156.json · all KEV CVEs
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Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.
Get the full file: Exploited Vulnerabilities Brief – September 2026 ($29): this month's KEV additions ranked by EPSS, ransomware use and due date, ready to hand to a patch team. Checkout by Polar.