CVE-2021-3156

7.8 HIGH CISA KEV - Actively Exploited
Published: January 26, 2021 Modified: November 10, 2025
View on NVD

Description

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.

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CVSS v3.x Details

0.0 Low Medium High Critical 10.0
Vector String
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

References to Advisories, Solutions, and Tools

Patch Vendor Advisory Exploit Third Party Advisory
http://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html
Source: cve@mitre.org
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html
Source: cve@mitre.org
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html
Source: cve@mitre.org
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html
Source: cve@mitre.org
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
Source: cve@mitre.org
Exploit Third Party Advisory VDB Entry
http://seclists.org/fulldisclosure/2021/Feb/42
Source: cve@mitre.org
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Jan/79
Source: cve@mitre.org
Exploit Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2024/Feb/3
Source: cve@mitre.org
Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/26/3
Source: cve@mitre.org
Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/27/1
Source: cve@mitre.org
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/27/2
Source: cve@mitre.org
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/02/15/1
Source: cve@mitre.org
Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/14/2
Source: cve@mitre.org
Mailing List Patch Third Party Advisory
http://www.openwall.com/lists/oss-security/2024/01/30/6
Source: cve@mitre.org
Exploit Mailing List
http://www.openwall.com/lists/oss-security/2024/01/30/8
Source: cve@mitre.org
Mailing List
https://kc.mcafee.com/corporate/index?page=content&id=SB10348
Source: cve@mitre.org
Broken Link Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/01/msg00022.html
Source: cve@mitre.org
Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CALA5FTXIQBRRYUA2ZQNJXB6OQMAXEII/
Source: cve@mitre.org
Mailing List Release Notes
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LHXK6ICO5AYLGFK2TAX5MZKUXTUKWOJY/
Source: cve@mitre.org
Mailing List Release Notes
https://security.gentoo.org/glsa/202101-33
Source: cve@mitre.org
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210128-0001/
Source: cve@mitre.org
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210128-0002/
Source: cve@mitre.org
Third Party Advisory
https://support.apple.com/kb/HT212177
Source: cve@mitre.org
Third Party Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sudo-privesc-jan2021-qnYQfcM
Source: cve@mitre.org
Third Party Advisory
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
Source: cve@mitre.org
Third Party Advisory
https://www.debian.org/security/2021/dsa-4839
Source: cve@mitre.org
Third Party Advisory
https://www.kb.cert.org/vuls/id/794544
Source: cve@mitre.org
Third Party Advisory US Government Resource
https://www.openwall.com/lists/oss-security/2021/01/26/3
Source: cve@mitre.org
Exploit Mailing List Third Party Advisory
https://www.oracle.com//security-alerts/cpujul2021.html
Source: cve@mitre.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html
Source: cve@mitre.org
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html
Source: cve@mitre.org
Patch Third Party Advisory
https://www.sudo.ws/stable.html#1.9.5p2
Source: cve@mitre.org
Release Notes
https://www.synology.com/security/advisory/Synology_SA_21_02
Source: cve@mitre.org
Third Party Advisory
https://www.vicarius.io/vsociety/posts/sudoedit-pwned-cve-2021-3156
Source: cve@mitre.org
Exploit Third Party Advisory
http://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Third Party Advisory VDB Entry
http://seclists.org/fulldisclosure/2021/Feb/42
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2021/Jan/79
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mailing List Third Party Advisory
http://seclists.org/fulldisclosure/2024/Feb/3
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/26/3
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/27/1
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/27/2
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/02/15/1
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/14/2
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Patch Third Party Advisory
http://www.openwall.com/lists/oss-security/2024/01/30/6
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mailing List
http://www.openwall.com/lists/oss-security/2024/01/30/8
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List
https://kc.mcafee.com/corporate/index?page=content&id=SB10348
Source: af854a3a-2127-422b-91ae-364da2661108
Broken Link Third Party Advisory
https://lists.debian.org/debian-lts-announce/2021/01/msg00022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Third Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CALA5FTXIQBRRYUA2ZQNJXB6OQMAXEII/
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Release Notes
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LHXK6ICO5AYLGFK2TAX5MZKUXTUKWOJY/
Source: af854a3a-2127-422b-91ae-364da2661108
Mailing List Release Notes
https://security.gentoo.org/glsa/202101-33
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210128-0001/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://security.netapp.com/advisory/ntap-20210128-0002/
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://support.apple.com/kb/HT212177
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sudo-privesc-jan2021-qnYQfcM
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
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
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.debian.org/security/2021/dsa-4839
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.kb.cert.org/vuls/id/794544
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory US Government Resource
https://www.openwall.com/lists/oss-security/2021/01/26/3
Source: af854a3a-2127-422b-91ae-364da2661108
Exploit Mailing List Third Party Advisory
https://www.oracle.com//security-alerts/cpujul2021.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuapr2022.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.oracle.com/security-alerts/cpuoct2021.html
Source: af854a3a-2127-422b-91ae-364da2661108
Patch Third Party Advisory
https://www.sudo.ws/stable.html#1.9.5p2
Source: af854a3a-2127-422b-91ae-364da2661108
Release Notes
https://www.synology.com/security/advisory/Synology_SA_21_02
Source: af854a3a-2127-422b-91ae-364da2661108
Third Party Advisory
https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3156
Source: 134c704f-9b21-4f2e-91b3-4a467353bcc0
US Government Resource

68 reference(s) from NVD

Quick Stats

CVSS v3 Score
7.8 / 10.0
EPSS (Exploit Probability)
92.5%
100th percentile
Exploitation Status
Actively Exploited
Remediation due: 2022-04-27

Weaknesses (CWE)

CWE-193 CWE-193

Affected Vendors

sudo_project debian beyondtrust fedoraproject mcafee oracle synology netapp

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