CVE-2021-3156
HIGHCISA KEVEPSS 100th pctlDescription
Sudo before 1.9.5p2 contains an off-by-one error that can result in a heap-based buffer overflow, which allows privilege escalation to root via "sudoedit -s" and a command-line argument that ends with a single backslash character.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Exploit Intelligence
Very high risk: more likely to be exploited than 100% of all known CVEs.
Sudo Heap-Based Buffer Overflow Vulnerability
Sudo contains an off-by-one error that can result in a heap-based buffer overflow, which allows for privilege escalation.
Apply updates per vendor instructions.
Remediation due: 2022-04-27
References
- http://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html
- http://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html
- http://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html
- http://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html
- http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
- http://seclists.org/fulldisclosure/2021/Feb/42
- http://seclists.org/fulldisclosure/2021/Jan/79
- http://seclists.org/fulldisclosure/2024/Feb/3
- http://www.openwall.com/lists/oss-security/2021/01/26/3
- http://www.openwall.com/lists/oss-security/2021/01/27/1
- http://www.openwall.com/lists/oss-security/2021/01/27/2
- http://www.openwall.com/lists/oss-security/2021/02/15/1
- http://www.openwall.com/lists/oss-security/2021/09/14/2
- http://www.openwall.com/lists/oss-security/2024/01/30/6
- http://www.openwall.com/lists/oss-security/2024/01/30/8
- https://kc.mcafee.com/corporate/index?page=content&id=SB10348
- https://lists.debian.org/debian-lts-announce/2021/01/msg00022.html
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CALA5FTXIQBRRYUA2ZQNJXB6OQMAXEII/
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LHXK6ICO5AYLGFK2TAX5MZKUXTUKWOJY/
- https://security.gentoo.org/glsa/202101-33
- https://security.netapp.com/advisory/ntap-20210128-0001/
- https://security.netapp.com/advisory/ntap-20210128-0002/
- https://support.apple.com/kb/HT212177
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sudo-privesc-jan2021-qnYQfcM
- https://www.beyondtrust.com/blog/entry/security-advisory-privilege-management-for-unix-linux-pmul-basic-and-privilege-management-for-mac-pmm-affected-by-sudo-vulnerability
- https://www.debian.org/security/2021/dsa-4839
- https://www.kb.cert.org/vuls/id/794544
- https://www.openwall.com/lists/oss-security/2021/01/26/3
- https://www.oracle.com//security-alerts/cpujul2021.html
- https://www.oracle.com/security-alerts/cpuapr2022.html
- https://www.oracle.com/security-alerts/cpuoct2021.html
- https://www.sudo.ws/stable.html#1.9.5p2
- https://www.synology.com/security/advisory/Synology_SA_21_02
- https://www.vicarius.io/vsociety/posts/sudoedit-pwned-cve-2021-3156
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Start freeThis product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2025-11-10.