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Vulnerability Intelligence

CVE-2021-3156 | Mondoo Vulnerability Intelligence

CVE-2021-3156

HIGH7.8

Sudo before 1

Published Jan 26, 2021

Modified 2 months ago

No fix available

Details

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.

References

WEBhttp://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html WEBhttp://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html WEBhttp://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html WEBhttp://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html WEBhttp://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html WEBhttp://seclists.org/fulldisclosure/2021/Feb/42 WEBhttp://seclists.org/fulldisclosure/2021/Jan/79 WEBhttp://seclists.org/fulldisclosure/2024/Feb/3 WEBhttp://www.openwall.com/lists/oss-security/2021/01/26/3 WEBhttp://www.openwall.com/lists/oss-security/2021/01/27/1 WEBhttp://www.openwall.com/lists/oss-security/2021/01/27/2 WEBhttp://www.openwall.com/lists/oss-security/2021/02/15/1 WEBhttp://www.openwall.com/lists/oss-security/2021/09/14/2 WEBhttp://www.openwall.com/lists/oss-security/2024/01/30/6 WEBhttp://www.openwall.com/lists/oss-security/2024/01/30/8 WEBhttps://kc.mcafee.com/corporate/index?page=content&id=SB10348 WEBhttps://lists.debian.org/debian-lts-announce/2021/01/msg00022.html ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CALA5FTXIQBRRYUA2ZQNJXB6OQMAXEII/ADVISORYhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/LHXK6ICO5AYLGFK2TAX5MZKUXTUKWOJY/ADVISORYhttps://security.gentoo.org/glsa/202101-33 WEBhttps://security.netapp.com/advisory/ntap-20210128-0001/WEBhttps://security.netapp.com/advisory/ntap-20210128-0002/WEBhttps://support.apple.com/kb/HT212177 ADVISORYhttps://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-sudo-privesc-jan2021-qnYQfcM WEBhttps://www.beyondtrust.com/blog/entry/security-advisory-privilege-management-for-unix-linux-pmul-basic-and-privilege-management-for-mac-pmm-affected-by-sudo-vulnerability WEBhttps://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-3156 ADVISORYhttps://www.cve.org/CVERecord?id=CVE-2021-3156 ADVISORYhttps://www.debian.org/security/2021/dsa-4839 ADVISORYhttps://www.kb.cert.org/vuls/id/794544 WEBhttps://www.openwall.com/lists/oss-security/2021/01/26/3 WEBhttps://www.oracle.com//security-alerts/cpujul2021.html WEBhttps://www.oracle.com/security-alerts/cpuapr2022.html WEBhttps://www.oracle.com/security-alerts/cpuoct2021.html WEBhttps://www.sudo.ws/stable.html#1.9.5p2 WEBhttps://www.synology.com/security/advisory/Synology_SA_21_02 WEBhttps://www.vicarius.io/vsociety/posts/sudoedit-pwned-cve-2021-3156

CVSS Analysis

CVSS v3.1

7.8

Exploitability

Attack Vector

LocalAV:L

Attack Complexity

LowAC:L

Privileges Required

LowPR:L

User Interaction

NoneUI:N

Scope

Scope

UnchangedS:U

Impact

Confidentiality

HighC:H

Integrity

HighI:H

Availability

HighA:H

7.8/CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Ecosystems

Timeline

PublishedJan 26, 2021

ModifiedOct 21, 2025