CVE-2021-3156
HighExploitedPublic exploitsudo - security update
Published Dec 1, 2021 · Updated Aug 4, 2026 · Also known as ALPINE-CVE-2021-3156, Baron Samedit, DEBIAN-CVE-2021-3156, DLA-2534-1, DSA-4839-1, SUSE-SU-2021:0928-1, SUSE-SU-2021:1267-1, SUSE-SU-2021:1273-1, SUSE-SU-2021:1274-1, SUSE-SU-2021:1275-1, SUSE-SU-2024:4389-1, Sudo Baron Samedit, TR-21-0077, TR-21-0700, TR-21-0960, TR-21-0961, UBUNTU-CVE-2021-3156, USN-4705-2
Key Facts
Patch immediately- CVE-2021-3156 is a high-severity vulnerability (CVSS 7.8 v3.1) affecting Privilege Management For Mac (Beyondtrust), Privilege Management For Unix\/linux (Beyondtrust), Web Gateway (Mcafee) and 22 more products.
- It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Apr 6, 2022. Public exploit code is available.
- EPSS estimates a 100% probability of exploitation in the next 30 days.
- Fixed versions are available, including Privilege Management For Mac 21.1.1, Privilege Management For Unix\/linux 10.3.2-10, Communications Performance Intelligence Center <=10.3.0.2.1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
CVSS v3.1
7.8
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
100%
Higher than 99.9% of all scored CVEs
Exploited in the wild
Yes
4 catalog listings
Public exploit code
Available
Proof-of-concept or weaponized module
Get the full CVE-2021-3156 brief as a PDF
Every affected product and fixed release, exploitation status and a first 24 hours response checklist, emailed within minutes.
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CISA KEV | Apr 6, 2022 | Apr 27, 2022 | Not reported |
| Industry KEV feed | Apr 6, 2022 | Apr 27, 2022 | Not reported |
| CIRCL KEV | Apr 6, 2022 | Apr 27, 2022 | Not reported |
| ENISA EUVD | Apr 6, 2022 | n/a | Not reported |
Required action: Apply updates per vendor instructions.
Affected Products
191 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| Privilege Management For MacBeyondtrust | See advisory | 21.1.1 |
| Privilege Management For Unix\/linuxBeyondtrust | See advisory | 10.3.2-10 |
| Web GatewayMcafee | 10.0.4, 8.2.17, 9.2.8 | n/a |
| Active Iq Unified ManagerNetapp | See advisory | n/a |
| Cloud BackupNetapp | See advisory | n/a |
Patched Releases
Privilege Management For Mac
21.1.1
Privilege Management For Unix\/linux
10.3.2-10
Communications Performance Intelligence Center
<=10.3.0.2.1
Micros Es400 Firmware
<=410
oracle micros workstation 6 firmware
<=655
Tekelec Platform Distribution
<=7.7.1
redhat-virtualization-host
0:4.3.13-20210127.0.el7_9, 0:4.4.4-20210201.0.el8_3
rootio-sudo
1.9.5p1-1.1
seal-sudo
1.8.23-10.el7_9.3+sp999
Sudo
0:1.8.23-4.el7_7.3, 0:1.8.25p1-8.el8_1.2, 0:1.8.6p3-29.el6_10.4, 1.8.10p3-10.29.1, 1.8.10p3-10.32.1, 1.8.10p3-10.35.1, 1.8.16-0ubuntu1.10, 1.8.19p1-2.1+deb9u3, 1.8.20p2-3.20.1, 1.8.20p2-3.23.1, 1.8.21p2-3ubuntu1.4, 1.8.22-4.15.1, 1.8.22-4.18.1, 1.8.22-lp151.5.12.1, 1.8.22-lp152.8.6.1, 1.8.22-lp152.8.9.1, 1.8.23-10.el7_9.1, 1.8.23-10.el7_9.3+sp999, 1.8.23-4.amzn2.2.1, 1.8.23-9.56.amzn1, 1.8.27-1+deb10u3, 1.8.27-4.15.1, 1.8.27-4.51.1, 1.8.27-4.6.1, 1.8.29-6.el8_3.1, 1.8.31-1ubuntu1.2, 1.8.31-r1, 1.8.6p3-29.0.3.el6_10.3, 1.8.9p5-1ubuntu1.5+esm6, 1.9.5_p2-r0, 1.9.5-2.ph1, 1.9.5-2.ph2, 1.9.5-2.ph3, 1.9.5.p2-1, 1.9.5p1-1.1, 1.9.5p2-r0, 1.9.7p2-1.4, NA, 1.8.32
sudo-devel
1.8.22-4.15.1, 1.8.22-4.18.1, 1.8.22-lp151.5.12.1, 1.8.22-lp152.8.6.1, 1.8.22-lp152.8.9.1, 1.8.23-10.el7_9.1, 1.8.23-4.amzn2.2.1, 1.8.23-9.56.amzn1, 1.8.27-4.15.1, 1.8.27-4.51.1, 1.8.27-4.6.1, 1.8.6p3-29.0.3.el6_10.3, 1.9.7p2-1.4
sudo-plugin-python
1.9.7p2-1.4
sudo-test
1.8.22-lp151.5.12.1, 1.8.22-lp152.8.6.1, 1.8.22-lp152.8.9.1, 1.9.7p2-1.4
Timeline
Publicly disclosed
Dec 1, 2021
Added to CISA KEV
Apr 6, 2022
Added to Industry KEV feed
Apr 6, 2022
Added to CIRCL KEV
Apr 6, 2022
Added to ENISA EUVD
Apr 6, 2022
Last updated
Aug 4, 2026
Weakness Type
- CWE-122 Heap-based Buffer Overflow
- CWE-193 Off-by-one Error
References
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14779
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14782
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14803
- advisoryhttp://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-27221
- advisoryhttps://9to5linux.com/another-sudo-root-privilege-escalation-vulnerability-got-patched-update-now
FAQ
Common Questions.
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.
Affected: Privilege Management For Mac (Beyondtrust); Privilege Management For Unix\/linux (Beyondtrust); Web Gateway (Mcafee) versions 10.0.4, 8.2.17, 9.2.8, among others. The full list is in the CVE brief.
It is exploited in the wild, listed in CISA KEV, Industry KEV feed, CIRCL KEV, ENISA EUVD since Apr 6, 2022.
Yes. It was added on Apr 6, 2022 with a federal remediation due date of Apr 27, 2022.
Public exploit code is available.
Fixed versions are available, including Privilege Management For Mac 21.1.1, Privilege Management For Unix\/linux 10.3.2-10, Communications Performance Intelligence Center <=10.3.0.2.1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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