`CVE-2021-3156` Sudo

Affected software	Sudo
Severity	7.8 High CVSS 3.1 3 scores
Weakness	CWE-193
Published	26 Jan 2021
Updated	17 Jun 2026

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.

Exploitation status

Exploited

Confirmed real-world exploitation.

CISA KEV listed Confirmed exploitation in the wild. Added 2022-04-06 · remediation due 2022-04-27 · ransomware use: unknown
VulnCheck KEV listed Exploitation reported in the wild. 11 citations · 82 exploits · earliest 2022-04-06.
CISA Vulnrichment exploitation: active CISA records active exploitation. Automatable: no, technical impact: total.
Indexed PoC 78 indexed Published artifacts you can open, in Exploit-DB, GitHub PoC, Metasploit, Nuclei; first seen 2021-01-26.
EPSS 99.9% chance in 30 days A model's forecast, not a report of exploitation. Higher than 99.9% of all scored CVEs.

VulnCheck KEV

Exploitation evidence from VulnCheck Known Exploited Vulnerabilities (VulnCheck KEV), used under VulnCheck's community terms. View CVE-2021-3156 in VulnCheck (free account), which lists 6 more citations and 77 more exploit references not shown here.

Evidence	Source	Detail	Date
Reported exploitation	cisa.gov	/sites/default/files/feeds/known_exploited_vulnerabilities.json	2022-04-06
Reported exploitation	cisa.gov	/news-events/alerts/2022/04/27/2021-top-routinely-exploited-vulnerabilities	2022-04-28
Reported exploitation	cisa.gov	/news-events/cybersecurity-advisories/aa22-117a	2022-04-28
Reported exploitation	ptsecurity.com	/ru-ru/research/pt-esc-threat-intelligence/ex-cobalt-go-red-tehnika-skrytogo-tunnelya	2024-06-06
Reported exploitation	ptsecurity.com	/ww-en/analytics/pt-esc-threat-intelligence/excobalt-gored-the-hidden-tunnel-technique	2024-06-19
Exploit reference	VulnCheck XDB 8486488deafe	Exploit type: local	2021-01-29
Exploit reference	VulnCheck XDB 3ee223200973	Exploit type: local	2021-01-30
Exploit reference	VulnCheck XDB 9fbcde6203e1	Exploit type: local	2021-01-30
Exploit reference	VulnCheck XDB b2ee85cf4e76	Exploit type: local	2021-01-31
Exploit reference	VulnCheck XDB b72767d3ef0b	Exploit type: local	2021-01-31

Evidence

Source

Detail

Date

Reported exploitation

cisa.gov

/sites/default/files/feeds/known_exploited_vulnerabilities.json

2022-04-06

Reported exploitation

cisa.gov

/news-events/alerts/2022/04/27/2021-top-routinely-exploited-vulnerabilities

2022-04-28

Reported exploitation

cisa.gov

/news-events/cybersecurity-advisories/aa22-117a

2022-04-28

Reported exploitation

ptsecurity.com

/ru-ru/research/pt-esc-threat-intelligence/ex-cobalt-go-red-tehnika-skrytogo-tunnelya

2024-06-06

Reported exploitation

ptsecurity.com

/ww-en/analytics/pt-esc-threat-intelligence/excobalt-gored-the-hidden-tunnel-technique

2024-06-19

Exploit reference

VulnCheck XDB 8486488deafe

Exploit type: local

2021-01-29

Exploit reference

VulnCheck XDB 3ee223200973

Exploit type: local

2021-01-30

Exploit reference

VulnCheck XDB 9fbcde6203e1

Exploit type: local

2021-01-30

Exploit reference

VulnCheck XDB b2ee85cf4e76

Exploit type: local

2021-01-31

Exploit reference

VulnCheck XDB b72767d3ef0b

Exploit type: local

2021-01-31

Index	Artifact	Stars	First seen
GitHub PoC	blasty/CVE-2021-3156	1,032	2021-01-30
Nuclei	Sudo Baron Samedit - Local Privilege Escalation
Exploit-DB	Sudo 1.9.5p1 - 'Baron Samedit ' Heap-Based Buffer Overflow Privilege Escalation (1)		2021-02-03
Metasploit	Sudo Heap-Based Buffer Overflow (excellent rank)
GitHub PoC	Sudo Baron Samedit Exploit	812	2021-03-15
Exploit-DB	Sudo 1.9.5p1 - 'Baron Samedit ' Heap-Based Buffer Overflow Privilege Escalation (2)		2021-02-03
GitHub PoC	PoC for CVE-2021-3156 (sudo heap overflow)	429	2021-01-30
GitHub PoC	CVE-2021-3156 - Sudo Baron Samedit	226	2021-04-29
GitHub PoC	CVE-2021-3156非交互式执行命令	204	2021-02-09
GitHub PoC	Root shell PoC for CVE-2021-3156	158	2021-02-03

Waratek protection

Outside Waratek scope

A Java vulnerability, but not one Waratek protects. It affects only Java on a user's desktop (applets, Web Start, JavaFX, the installer), sits in a product the Waratek agent can't be installed into, or is in a package we don't expect in business applications. The decision below says which.

Protection none
Action not pursued none
Review human Researcher
Record active

Decided by	Manual classification of this CVE in the legacy dataset
Finding	A manual classification set this CVE's status to Outside Waratek scope, but the CVE names a tracked product.

Decided by

Manual classification of this CVE in the legacy dataset

Finding

A manual classification set this CVE's status to Outside Waratek scope, but the CVE names a tracked product.

CVSS

7.8 HIGH v3.1 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H 3 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

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

CVSS 3.1 7.8 HIGH CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CISA-ADP Secondary

CVSS 2.0 7.2 none AV:L/AC:L/Au:N/C:C/I:C/A:C NVD Primary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	7.8	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`	NVD	Primary	published
CVSS 3.1	7.8	HIGH	`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`	CISA-ADP	Secondary
CVSS 2.0	7.2	none	`AV:L/AC:L/Au:N/C:C/I:C/A:C`	NVD	Primary

Affected software and releases

Oracle advisories

Advisory	Type	Quarter	Products Oracle names in its risk matrix
Oracle Critical Patch Update April 2022 ↗	CPU	2022-Q2	Oracle Communications / Platform (Sudo) (10.3.0.0.0-10.3.0.2.1, 10.4.0.1.0-10.4.0.3.1)
Oracle Critical Patch Update October 2021 ↗	CPU	2021-Q4	Oracle Communications / Storage Management (Sudo) (7.4.0-7.7.1)
Oracle Critical Patch Update July 2021 ↗	CPU	2021-Q3	Oracle Food and Beverage Applications / Express Station 4 (Sudo) (400-410) Oracle Food and Beverage Applications / Kitchen Display System 210 (Sudo) (210) Oracle Food and Beverage Applications / Workstation 310 (Sudo) (310) Oracle Food and Beverage Applications / Workstation 5A (Sudo) (5A) Oracle Food and Beverage Applications / Workstation 6 (Sudo) (610-655)

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update April 2022 ↗

CPU

2022-Q2

Oracle Communications / Platform (Sudo) (10.3.0.0.0-10.3.0.2.1, 10.4.0.1.0-10.4.0.3.1)

Oracle Critical Patch Update October 2021 ↗

CPU

2021-Q4

Oracle Communications / Storage Management (Sudo) (7.4.0-7.7.1)

Oracle Critical Patch Update July 2021 ↗

CPU

2021-Q3

Oracle Food and Beverage Applications / Express Station 4 (Sudo) (400-410)
Oracle Food and Beverage Applications / Kitchen Display System 210 (Sudo) (210)
Oracle Food and Beverage Applications / Workstation 310 (Sudo) (310)
Oracle Food and Beverage Applications / Workstation 5A (Sudo) (5A)
Oracle Food and Beverage Applications / Workstation 6 (Sudo) (610-655)

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Communications	Platform (Sudo)	10.3.0.0.0-10.3.0.2.1, 10.4.0.1.0-10.4.0.3.1
Oracle Communications	Storage Management (Sudo)	7.4.0-7.7.1
Oracle Food and Beverage Applications	Express Station 4 (Sudo)	400-410
Oracle Food and Beverage Applications	Kitchen Display System 210 (Sudo)	210	210
Oracle Food and Beverage Applications	Workstation 310 (Sudo)	310	310
Oracle Food and Beverage Applications	Workstation 5A (Sudo)	5A	5
Oracle Food and Beverage Applications	Workstation 6 (Sudo)	610-655

Family

Component

Versions, as Oracle lists them

Read as

Oracle Communications

Platform (Sudo)

10.3.0.0.0-10.3.0.2.1, 10.4.0.1.0-10.4.0.3.1

Oracle Communications

Storage Management (Sudo)

7.4.0-7.7.1

Oracle Food and Beverage Applications

Express Station 4 (Sudo)

400-410

Oracle Food and Beverage Applications

Kitchen Display System 210 (Sudo)

210

Oracle Food and Beverage Applications

Workstation 310 (Sudo)

310

Oracle Food and Beverage Applications

Workstation 5A (Sudo)

Oracle Food and Beverage Applications

Workstation 6 (Sudo)

610-655

Products and versions

24 products, 32 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	beyondtrust	privilege management for mac	generic	＜ 21.1.1
nvd	beyondtrust	privilege management for unix\/linux	generic	＜ 10.3.2.10
nvd	debian	debian linux	generic	9.0 · 10.0
nvd	fedoraproject	fedora	generic	32 · 33
nvd	mcafee	web gateway	generic	8.2.17 · 9.2.8 · 10.0.4
nvd	netapp	active iq unified manager	generic	any version
nvd	netapp	cloud backup	generic	any version
nvd	netapp	hci management node	generic	any version
nvd	netapp	oncommand unified manager core package	generic	any version
nvd	netapp	ontap select deploy administration utility	generic	any version
nvd	netapp	ontap tools	generic	9
nvd	netapp	solidfire	generic	any version
nvd	oracle	communications performance intelligence center	generic	≥ 10.3.0.0.0 and ≤ 10.3.0.2.1 · ≥ 10.4.0.1.0 and ≤ 10.4.0.3.1
nvd	oracle	micros compact workstation 3 firmware	generic	310
nvd	oracle	micros es400 firmware	generic	≥ 400 and ≤ 410
nvd	oracle	micros kitchen display system firmware	generic	210
nvd	oracle	micros workstation 5a firmware	generic	5a
nvd	oracle	micros workstation 6 firmware	generic	≥ 610 and ≤ 655
nvd	oracle	tekelec platform distribution	generic	≥ 7.4.0 and ≤ 7.7.1
nvd	sudo project	sudo	generic	≥ 1.8.2 and ＜ 1.8.32 · ≥ 1.9.0 and ＜ 1.9.5 · 1.9.5 · 1.9.5:patch1
nvd	synology	diskstation manager	generic	6.2
nvd	synology	diskstation manager unified controller	generic	3.0
nvd	synology	skynas firmware	generic	any version
nvd	synology	vs960hd firmware	generic	any version

Source

Vendor

Product

Scheme

Affected versions

nvd

beyondtrust

privilege management for mac

generic

＜ 21.1.1

nvd

beyondtrust

privilege management for unix\/linux

generic

＜ 10.3.2.10

nvd

debian

debian linux

generic

9.0 · 10.0

nvd

fedoraproject

fedora

generic

32 · 33

nvd

mcafee

web gateway

generic

8.2.17 · 9.2.8 · 10.0.4

nvd

netapp

active iq unified manager

generic

any version

nvd

netapp

cloud backup

generic

any version

nvd

netapp

hci management node

generic

any version

nvd

netapp

oncommand unified manager core package

generic

any version

nvd

netapp

ontap select deploy administration utility

generic

any version

nvd

netapp

ontap tools

generic

nvd

netapp

solidfire

generic

any version

nvd

oracle

communications performance intelligence center

generic

≥ 10.3.0.0.0 and ≤ 10.3.0.2.1 · ≥ 10.4.0.1.0 and ≤ 10.4.0.3.1

nvd

oracle

micros compact workstation 3 firmware

generic

310

nvd

oracle

micros es400 firmware

generic

≥ 400 and ≤ 410

nvd

oracle

micros kitchen display system firmware

generic

210

nvd

oracle

micros workstation 5a firmware

generic

nvd

oracle

micros workstation 6 firmware

generic

≥ 610 and ≤ 655

nvd

oracle

tekelec platform distribution

generic

≥ 7.4.0 and ≤ 7.7.1

nvd

sudo project

sudo

generic

≥ 1.8.2 and ＜ 1.8.32 · ≥ 1.9.0 and ＜ 1.9.5 · 1.9.5 · 1.9.5:patch1

nvd

synology

diskstation manager

generic

6.2

nvd

synology

diskstation manager unified controller

generic

3.0

nvd

synology

skynas firmware

generic

any version

nvd

synology

vs960hd firmware

generic

any version

Earlier manual review

A reviewer classified this CVE in an older dataset. We kept the labels and products below, but not the reviewer's reasoning.

## Manual Classification Context **Labels:** EXPRESS STATION 4 (SUDO), WORKSTATION 6 (SUDO), WORKSTATION 5A (SUDO), WORKSTATION 310 (SUDO), KITCHEN DISPLAY SYSTEM 210 (SUDO), STORAGE MANAGEMENT (SUDO) **Products:** ORACLE FOOD AND BEVERAGE APPLICATIONS, MICROS WORKSTATION 6, MICROS COMPACT WORKSTATION 3, MICROS WORKSTATION 5A, MICROS ES400 SERIES, MICROS KITCHEN DISPLAY SYSTEM HARDWARE, TEKELEC PLATFORM DISTRIBUTION, ORACLE COMMUNICATIONS

References

URL	Tags
http://packetstormsecurity.com/files/161160/Sudo-Heap-Based-Buffer-Overflow.html	Exploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/161230/Sudo-Buffer-Overflow-Privilege-Escalation.html	Exploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/161270/Sudo-1.9.5p1-Buffer-Overflow-Privilege-Escalation.html	Exploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/161293/Sudo-1.8.31p2-1.9.5p1-Buffer-Overflow.html	Exploit, Third Party Advisory, VDB Entry
http://packetstormsecurity.com/files/176932/glibc-syslog-Heap-Based-Buffer-Overflow.html	Exploit, Third Party Advisory, VDB Entry
http://seclists.org/fulldisclosure/2021/Feb/42	Mailing List, Third Party Advisory
http://seclists.org/fulldisclosure/2021/Jan/79	Exploit, Mailing List, Third Party Advisory
http://seclists.org/fulldisclosure/2024/Feb/3	Exploit, Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/26/3	Exploit, Mailing List, Third Party Advisory
http://www.openwall.com/lists/oss-security/2021/01/27/1	Mailing List, Third Party Advisory

URL

Timeline

Published	2021-01-26	By the CVE Program.
Added to CISA KEV	2022-04-06	Listed in CISA's Known Exploited Vulnerabilities catalog.
VulnCheck KEV: earliest evidence	2022-04-06	Date of the oldest evidence of exploitation in VulnCheck KEV's record. VulnCheck does not publish the date it listed the CVE.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.
VulnCheck KEV: latest evidence	2026-10-31	Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.

Published

2021-01-26

By the CVE Program.

Added to CISA KEV

2022-04-06

Listed in CISA's Known Exploited Vulnerabilities catalog.

VulnCheck KEV: earliest evidence

2022-04-06

Date of the oldest evidence of exploitation in VulnCheck KEV's record. VulnCheck does not publish the date it listed the CVE.

NVD record modified

2026-06-17

NVD's own last-modified date for this record.

VulnCheck KEV: latest evidence

2026-10-31

Date of the newest report, exploit reference or honeypot sighting in VulnCheck KEV's record.

How VRT decided (5 of 24 rules ran)

5 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification decided it matched Outside Waratek scope Found in legacy manual classifications

6 non-java-upstream not reached A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component not reached The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side not reached Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven not reached An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

NVD ↗ · CVE.org ↗