CVE-2021-3156

7.8 HIGH

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 ro...

Published: 2021-01-26 · Last updated: 2026-06-17

Severity and scoring

CVSS: 7.8 HIGH
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CWE: CWE-193

Affected products

Vendor	Product
beyondtrust	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
debian	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
fedoraproject	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
mcafee	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
netapp	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
oracle	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
sudo_project	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center
synology	active_iq_unified_manager, cloud_backup, communications_performance_intelligence_center

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.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-3156
[Exploit reference]http://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html
[Exploit reference]http://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html
[Exploit reference]http://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html
[Exploit reference]http://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html
[Exploit reference]http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
[Other]http://seclists.org/fulldisclosure/2021/Feb/42
[Exploit reference]http://seclists.org/fulldisclosure/2021/Jan/79
[Exploit reference]http://seclists.org/fulldisclosure/2024/Feb/3
[Exploit reference]http://www.openwall.com/lists/oss-security/2021/01/26/3
[Other]http://www.openwall.com/lists/oss-security/2021/01/27/1
[Other]http://www.openwall.com/lists/oss-security/2021/01/27/2
[Exploit reference]http://www.openwall.com/lists/oss-security/2021/02/15/1
[Patch]http://www.openwall.com/lists/oss-security/2021/09/14/2
[Exploit reference]http://www.openwall.com/lists/oss-security/2024/01/30/6
[Other]http://www.openwall.com/lists/oss-security/2024/01/30/8
[Other]https://kc.mcafee.com/corporate/index?page=content&id=SB10348
[Other]https://lists.debian.org/debian-lts-announce/2021/01/msg00022.html
[Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CALA5FTXIQBRRYUA2ZQNJXB6OQMAXEII/
[Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LHXK6ICO5AYLGFK2TAX5MZKUXTUKWOJY/
[Other]https://security.gentoo.org/glsa/202101-33
[Other]https://security.netapp.com/advisory/ntap-20210128-0001/
[Other]https://security.netapp.com/advisory/ntap-20210128-0002/
[Other]https://support.apple.com/kb/HT212177
[Other]https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sudo-privesc-jan2021-qnYQfcM
[Other]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
[Other]https://www.debian.org/security/2021/dsa-4839
[Other]https://www.kb.cert.org/vuls/id/794544
[Exploit reference]https://www.openwall.com/lists/oss-security/2021/01/26/3
[Patch]https://www.oracle.com//security-alerts/cpujul2021.html
[Patch]https://www.oracle.com/security-alerts/cpuapr2022.html
[Patch]https://www.oracle.com/security-alerts/cpuoct2021.html
[Other]https://www.sudo.ws/stable.html#1.9.5p2
[Other]https://www.synology.com/security/advisory/Synology_SA_21_02
[Exploit reference]https://www.vicarius.io/vsociety/posts/sudoedit-pwned-cve-2021-3156
[Exploit reference]http://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html
[Exploit reference]http://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html
[Exploit reference]http://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html
[Exploit reference]http://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html
[Exploit reference]http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html
[Other]http://seclists.org/fulldisclosure/2021/Feb/42
[Exploit reference]http://seclists.org/fulldisclosure/2021/Jan/79
[Exploit reference]http://seclists.org/fulldisclosure/2024/Feb/3
[Exploit reference]http://www.openwall.com/lists/oss-security/2021/01/26/3
[Other]http://www.openwall.com/lists/oss-security/2021/01/27/1
[Other]http://www.openwall.com/lists/oss-security/2021/01/27/2
[Exploit reference]http://www.openwall.com/lists/oss-security/2021/02/15/1
[Patch]http://www.openwall.com/lists/oss-security/2021/09/14/2
[Exploit reference]http://www.openwall.com/lists/oss-security/2024/01/30/6
[Other]http://www.openwall.com/lists/oss-security/2024/01/30/8
[Other]https://kc.mcafee.com/corporate/index?page=content&id=SB10348
[Other]https://lists.debian.org/debian-lts-announce/2021/01/msg00022.html
[Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CALA5FTXIQBRRYUA2ZQNJXB6OQMAXEII/
[Other]https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LHXK6ICO5AYLGFK2TAX5MZKUXTUKWOJY/
[Other]https://security.gentoo.org/glsa/202101-33
[Other]https://security.netapp.com/advisory/ntap-20210128-0001/
[Other]https://security.netapp.com/advisory/ntap-20210128-0002/
[Other]https://support.apple.com/kb/HT212177
[Other]https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sudo-privesc-jan2021-qnYQfcM
[Other]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
[Other]https://www.debian.org/security/2021/dsa-4839
[Other]https://www.kb.cert.org/vuls/id/794544
[Exploit reference]https://www.openwall.com/lists/oss-security/2021/01/26/3
[Patch]https://www.oracle.com//security-alerts/cpujul2021.html
[Patch]https://www.oracle.com/security-alerts/cpuapr2022.html
[Patch]https://www.oracle.com/security-alerts/cpuoct2021.html
[Other]https://www.sudo.ws/stable.html#1.9.5p2
[Other]https://www.synology.com/security/advisory/Synology_SA_21_02
[Other]https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3156

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