BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2021
CVE-2021-3156High confidence

Sudo Heap-Based Buffer Overflow Vulnerability

Sudo · Sudo

7.8HighCVSS 3.1
Recommended action
Patch now

CISA confirms exploitation in the wild and lists 2022-04-27 as the remediation due date.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityHighOperational priority:Critical, raised one band.upgradedsince 6 Apr 2022

Evidence used

  • CISA confirms exploitation in the wild.
  • A structured source references public exploit or proof-of-concept material.
  • Exploitation requires an existing local or physical foothold with privileges.
  • EPSS is 99.96% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs Sudo Sudo and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Distribution package intelligence

Release-specific package status

Alpine, Debian findings are scoped to the named distribution, release and source package. An absent finding does not mean a package is unaffected.

7 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Distribution releaseSource packageVendor stateFixed versionEvidence
Alpine v3.23v3.23 · communitysudoVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.1.9.5_p2-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.22v3.22 · communitysudoVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.1.9.5_p2-r0Alpine Security Database ↗Source updated 11 Sep 2026
Alpine v3.21v3.21 · communitysudoVendor fix publishedAlpine records a security fix at this version. An absent entry does not mean the package is unaffected.1.9.5_p2-r0Alpine Security Database ↗Source updated 19 Aug 2026
Debian trixietrixie · sourcesudoVendor fix publishedDebian records a fixed source-package version for this release.1.9.5p1-1.1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian bookwormbookworm · sourcesudoVendor fix publishedDebian records a fixed source-package version for this release.1.9.5p1-1.1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian forkyforky · sourcesudoVendor fix publishedDebian records a fixed source-package version for this release.1.9.5p1-1.1Debian Security Tracker ↗Source updated 5 Oct 2026
Debian sidsid · sourcesudoVendor fix publishedDebian records a fixed source-package version for this release.1.9.5p1-1.1Debian Security Tracker ↗Source updated 5 Oct 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2021-26500

CISA KEV mirrored by ENISA

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.

EUVD state
Present in the current official mapping
Known exploitation
Recorded by ENISA since 6 Apr 2022. Evidence sources: cisa_kev.
ENISA score
7.8 · CVSS 3.1
Advisory evidence
34 linked advisory records
Explicit mitigation evidence

Only statements that explicitly mention a fix, patch, update, workaround or mitigation are shown here.

  • csaf_redhat · RHSA-2021:0219Red Hat Security Advisory: sudo security update
  • csaf_suse · SUSE-SU-2021:0928-1Security update for sudo
  • csaf_opensuse · openSUSE-SU-2021:0169-1Security update for sudo
  • csaf_suse · SUSE-SU-2021:0227-1Security update for sudo
  • csaf_redhat · RHSA-2021:0226Red Hat Security Advisory: sudo security update
  • csaf_redhat · RHSA-2021:0401Red Hat Security Advisory: Red Hat Virtualization Host security bug fix and enhancement update [ovirt-4.4.4]
  • csaf_opensuse · openSUSE-SU-2021:0602-1Security update for sudo
  • csaf_suse · SUSE-SU-2021:1267-1Security update for sudo
  • csaf_opensuse · openSUSE-SU-2021:0170-1Security update for sudo
  • csaf_suse · SUSE-SU-2024:4389-1Security update for sudo
  • csaf_redhat · RHSA-2021:0225Red Hat Security Advisory: sudo security update
  • csaf_redhat · RHSA-2021:0223Red Hat Security Advisory: sudo security update
  • csaf_suse · SUSE-SU-2021:0225-1Security update for sudo
  • csaf_suse · SUSE-SU-2021:0226-1Security update for sudo
  • csaf_redhat · RHSA-2021:0224Red Hat Security Advisory: sudo security update
  • csaf_suse · SUSE-SU-2021:1273-1Security update for sudo
  • csaf_suse · SUSE-SU-2021:1275-1Security update for sudo
  • csaf_redhat · RHSA-2021:0395Red Hat Security Advisory: RHV-H security, bug fix, enhancement update (redhat-virtualization-host) 4.3.13
  • csaf_redhat · RHSA-2021:0220Red Hat Security Advisory: sudo security update
  • csaf_suse · SUSE-SU-2021:0232-1Security update for sudo
  • csaf_redhat · RHSA-2021:0218Red Hat Security Advisory: sudo security update
  • csaf_suse · SUSE-SU-2021:1274-1Security update for sudo
  • csaf_redhat · RHSA-2021:0221Red Hat Security Advisory: sudo security update
  • csaf_redhat · RHSA-2021:0227Red Hat Security Advisory: sudo security update
  • csaf_redhat · RHSA-2021:0222Red Hat Security Advisory: sudo security update
Recommended actionPatch now

CISA confirms exploitation in the wild and lists 2022-04-27 as the remediation due date.

Patch available
01

What, why and how

Sudo contains an off-by-one error that can result in a heap-based buffer overflow, which allows for privilege escalation.

What

Sudo contains an off-by-one error that can result in a heap-based buffer overflow, which allows for privilege escalation.

Why

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.

What

Sudo contains an off-by-one error that can result in a heap-based buffer overflow, which allows for privilege escalation.

Why

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may gain additional privileges.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Confirmed in the wild

CISA added this CVE to its Known Exploited Vulnerabilities catalogue on 2022-04-06.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

A structured CVE source labels at least one public reference as exploit material. BlackTree has not independently validated that it is safe, reliable or weaponised.

Likely attack path
local access → Off-by-one Error → gain additional privileges
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-193 ↗

CWE-193: Off-by-one Error. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRLowPrivileges required: The attacker needs basic user-level privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CHighConfidentiality impact: A successful attack can cause a major loss.IHighIntegrity impact: A successful attack can cause a major loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
Privilege escalationCWE-193CISA KEVPublic exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2021-26500Known-exploited evidence recorded

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.

Official EUVD record ↗
BSI · German · WID-SEC-2023-0066sudo: Schwachstelle ermöglicht Privilegieneskalation

Ein lokaler Angreifer kann eine Schwachstelle in sudo ausnutzen, um seine Privilegien zu erhöhen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20210127Security Bulletin 27 Jan 2021

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 27 Jan 2021, published on 27 January 2021. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0508Multiples vulnérabilités dans les produits Moxa

De multiples vulnérabilités ont été découvertes dans les produits Moxa. Elles permettent à un attaquant de provoquer une injection de code indirecte à distance (XSS) et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0504Multiples vulnérabilités dans les produits IBM

curité IBM 7005519 du 26 juin 2023 https://www.ibm.com/support/pages/node/7005519 Bulletin de sécurité IBM 7008449 du 29 juin 2023 https://www.ibm.com/support/pages/node/7008449 Référence CVE CVE-2014-3577 https://www.cve.org/CVERecord?id=CVE-2014-3577 Référence CVE CVE-2019-10743 https://www.cve.org/CVERecord?id=CVE-2019-10743 Référence CVE CVE-2019-18634 https://www.cve.org/CVERecord?id=CVE-2019-18634 Référence CVE CVE-2019-19232 https://www.cve.org/CVERecord?id=CVE-2019-19232 Référence CVE CVE-2019-19234 https://www.cve.org/CVERecord?id=CVE-2019-19234 Référence CVE CVE-2020-8244 https://www.cve.org/CVERecord?id=CVE-2020-8244 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Référence CVE CVE-2022-1471 https://www.cve.org/CVERecord?id=CVE-2022-1471 Référence CVE CVE-2022-25857 https://www.cve.org/CVERecord?id=CVE-2022-25857 Référence CVE CVE-2022-25881 https://www.cve.org/CVERecord?id=CVE-2022-25881 Référence CVE CVE-2022-33980 https://www.cve.org/CVERecord?id=CVE-2022-33980 Référence CVE CVE-2022-37865 https://www.cve.org/CVERecord?id=CVE-2022-37865 Référence CVE CVE-2022-37866 https://www.cve.org/CVERecord?id=CVE-2022-37866 Référence CVE CVE-2022-38749 https://www.cve.org/CVERecord?id=CVE-2022-38749 Référence CVE CVE-2022-38750 https://www.cve.org/CVERecord?id=CVE

Official advisory ↗
CERT-FR · French · CERTFR-2023-AVI-0051Multiples vulnérabilités dans les produits Juniper

d?id=CVE-2021-26691 Référence CVE CVE-2021-27219 https://www.cve.org/CVERecord?id=CVE-2021-27219 Référence CVE CVE-2021-27363 https://www.cve.org/CVERecord?id=CVE-2021-27363 Référence CVE CVE-2021-27364 https://www.cve.org/CVERecord?id=CVE-2021-27364 Référence CVE CVE-2021-27365 https://www.cve.org/CVERecord?id=CVE-2021-27365 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=CVE-2021-29154 Référence CVE CVE-2021-29650 https://www.cve.org/CVERecord?id=CVE-2021-29650 Référence CVE CVE-2021-30465 https://www.cve.org/CVERecord?id=CVE-2021-30465 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Référence CVE CVE-2021-3177 https://www.cve.org/CVERecord?id=CVE-2021-3177 Référence CVE CVE-2021-32399 https://www.cve.org/CVERecord?id=CVE-2021-32399 Référence CVE CVE-2021-33033 https://www.cve.org/CVERecord?id=CVE-2021-33033 Référence CVE CVE-2021-33034 https://www.cve.org/CVERecord?id=CVE-2021-33034 Référence CVE CVE-2021-3347 https://www.cve.org/CVERecord?id=CVE-2021-3347 Référence CVE CVE-2021-33909 https://www.cve.org/CVERecord?id=CVE-2021-33909 Référence CVE CVE-2021-3450 https://www.cve.org/CVERecord?id=CVE-2021-3450 Référence CVE CVE-2021-34798 https://www.cve.org/CVERecord?id=CVE-202

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-425Multiples vulnérabilités dans IBM Spectrum Protect Plus

De multiples vulnérabilités ont été découvertes dans IBM Spectrum Protect Plus. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service à distance, un contournement de la politique de sécurité et une atteinte à l'intégrité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-351Multiples vulnérabilités dans les logiciels Juniper

-Security-Bulletin-Contrail-Service-Orchestration-An-authenticated-local-user-may-have-their-permissions-elevated-via-the-device-via-management-interface-without-authentication-CVE-2022-22189?language=en_US Bulletin de sécurité Juniper JSA69500 du 13 avril 2022 https://supportportal.juniper.net/s/article/2022-04-Security-Bulletin-Paragon-Active-Assurance-Control-Center-Information-disclosure-vulnerability-in-crafted-URL-CVE-2022-22190?language=en_US Bulletin de sécurité Juniper JSA69504 du 13 avril 2022 https://supportportal.juniper.net/s/article/2022-04-Security-Bulletin-Juniper-Secure-Analytics-JSA-Series-Heap-Based-Buffer-Overflow-in-Sudo-CVE-2021-3156?language=en_US Bulletin de sécurité Juniper JSA69506 du 13 avril 2022 https://supportportal.juniper.net/s/article/2022-04-Security-Bulletin-Paragon-Active-Assurance-Local-Privilege-Escalation-in-polkits-pkexec-CVE-2021-4034?language=en_US Bulletin de sécurité Juniper JSA69507 du 13 avril 2022 https://supportportal.juniper.net/s/article/2022-04-Security-Bulletin-Contrail-Networking-Multiple-vulnerabilities-resolved-in-Contrail-Networking-21-3-CVE-yyyy-nnnn?language=en_US Bulletin de sécurité Juniper JSA69510 du 13 avril 2022 https://supportportal.juniper.net/s/article/2022-04-Security-Bulletin-Contrail-Networking-Multiple-Vulnerabilities-have

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-267Multiples vulnérabilités dans Juniper Networks Junos Space

e.org/CVERecord?id=CVE-2020-25637 Référence CVE CVE-2020-25643 https://www.cve.org/CVERecord?id=CVE-2020-25643 Référence CVE CVE-2020-2732 https://www.cve.org/CVERecord?id=CVE-2020-2732 Référence CVE CVE-2020-5208 https://www.cve.org/CVERecord?id=CVE-2020-5208 Référence CVE CVE-2020-6829 https://www.cve.org/CVERecord?id=CVE-2020-6829 Référence CVE CVE-2020-7039 https://www.cve.org/CVERecord?id=CVE-2020-7039 Référence CVE CVE-2020-8647 https://www.cve.org/CVERecord?id=CVE-2020-8647 Référence CVE CVE-2020-8649 https://www.cve.org/CVERecord?id=CVE-2020-8649 Référence CVE CVE-2020-9383 https://www.cve.org/CVERecord?id=CVE-2020-9383 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Référence CVE CVE-2021-3396 https://www.cve.org/CVERecord?id=CVE-2021-3396 Gestion détaillée du document le 23 mars 2022 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèmes d'information

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-239Multiples vulnérabilités dans les produits IBM

ecord?id=CVE-2020-35508 Référence CVE CVE-2020-35513 https://www.cve.org/CVERecord?id=CVE-2020-35513 Référence CVE CVE-2020-8492 https://www.cve.org/CVERecord?id=CVE-2020-8492 Référence CVE CVE-2021-20373 https://www.cve.org/CVERecord?id=CVE-2021-20373 Référence CVE CVE-2021-23214 https://www.cve.org/CVERecord?id=CVE-2021-23214 Référence CVE CVE-2021-23222 https://www.cve.org/CVERecord?id=CVE-2021-23222 Référence CVE CVE-2021-23727 https://www.cve.org/CVERecord?id=CVE-2021-23727 Référence CVE CVE-2021-29678 https://www.cve.org/CVERecord?id=CVE-2021-29678 Référence CVE CVE-2021-3139 https://www.cve.org/CVERecord?id=CVE-2021-3139 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Référence CVE CVE-2021-33026 https://www.cve.org/CVERecord?id=CVE-2021-33026 Référence CVE CVE-2021-35517 https://www.cve.org/CVERecord?id=CVE-2021-35517 Référence CVE CVE-2021-35578 https://www.cve.org/CVERecord?id=CVE-2021-35578 Référence CVE CVE-2021-36090 https://www.cve.org/CVERecord?id=CVE-2021-36090 Référence CVE CVE-2021-3712 https://www.cve.org/CVERecord?id=CVE-2021-3712 Référence CVE CVE-2021-38926 https://www.cve.org/CVERecord?id=CVE-2021-38926 Référence CVE CVE-2021-38931 https://www.cve.org/CVERecord?id=CVE-2021-38931 Référence CVE CVE-2021-38951 https://www.cve.org/CVERecord?id=CVE

Official advisory ↗
CERT-FR · French · CERTFR-2022-AVI-092Multiples vulnérabilités dans IBM Spectrum Protect Plus

De multiples vulnérabilités ont été découvertes dans IBM Spectrum Protect Plus. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire, un déni de service à distance et un contournement de la politique de sécurité.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-700Multiples vulnérabilités dans les produits IBM

rd?id=CVE-2020-8450 Référence CVE CVE-2021-20385 https://www.cve.org/CVERecord?id=CVE-2021-20385 Référence CVE CVE-2021-20386 https://www.cve.org/CVERecord?id=CVE-2021-20386 Référence CVE CVE-2021-20389 https://www.cve.org/CVERecord?id=CVE-2021-20389 Référence CVE CVE-2021-20419 https://www.cve.org/CVERecord?id=CVE-2021-20419 Référence CVE CVE-2021-20426 https://www.cve.org/CVERecord?id=CVE-2021-20426 Référence CVE CVE-2021-20428 https://www.cve.org/CVERecord?id=CVE-2021-20428 Référence CVE CVE-2021-21284 https://www.cve.org/CVERecord?id=CVE-2021-21284 Référence CVE CVE-2021-21285 https://www.cve.org/CVERecord?id=CVE-2021-21285 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Gestion détaillée du document le 14 septembre 2021 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèmes d'information

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-637Multiples vulnérabilités dans Aruba AirWave Management Platform

De multiples vulnérabilités ont été découvertes dans Aruba AirWave Management Platform. Elles permettent à un attaquant de provoquer une élévation de privilèges et une injection de code indirecte à distance (XSS).

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-597Vulnérabilité dans Aruba ALE

Une vulnérabilité a été découverte dans Aruba ALE. Elle permet à un attaquant de provoquer une élévation de privilèges.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-589Multiples vulnérabilités dans Juniper Junos Space Log Collector

ecord?id=CVE-2020-28374 Référence CVE CVE-2020-29573 https://www.cve.org/CVERecord?id=CVE-2020-29573 Référence CVE CVE-2020-29661 https://www.cve.org/CVERecord?id=CVE-2020-29661 Référence CVE CVE-2020-7595 https://www.cve.org/CVERecord?id=CVE-2020-7595 Référence CVE CVE-2020-8625 https://www.cve.org/CVERecord?id=CVE-2020-8625 Référence CVE CVE-2021-20225 https://www.cve.org/CVERecord?id=CVE-2021-20225 Référence CVE CVE-2021-20233 https://www.cve.org/CVERecord?id=CVE-2021-20233 Référence CVE CVE-2021-20265 https://www.cve.org/CVERecord?id=CVE-2021-20265 Référence CVE CVE-2021-20305 https://www.cve.org/CVERecord?id=CVE-2021-20305 Référence CVE CVE-2021-3156 https://www.cve.org/CVERecord?id=CVE-2021-3156 Gestion détaillée du document le 03 août 2021 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos Contact cyber.gouv.fr service-public.fr legifrance.gouv.fr info.gouv.fr france.fr info.gouv.fr/risques Premier Ministre / Secrétariat Général de la Défense et de la Sécurité Nationale / Agence nationale de la sécurité des systèmes d'information

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-496Multiples vulnérabilités dans Aruba ClearPass Policy Manager

De multiples vulnérabilités ont été découvertes dans Aruba ClearPass Policy Manager. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à l'intégrité des données.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-127Vulnérabilité dans les produits Moxa

Une vulnérabilité a été découverte dans les produits Moxa. Elle permet à un attaquant de provoquer une élévation de privilèges.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-108Vulnérabilité dans les produits Cisco

Une vulnérabilité a été découverte dans les produits Cisco. Elle permet à un attaquant de provoquer une élévation de privilèges.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-098Multiples vulnérabilités dans Apple macOS

De multiples vulnérabilités ont été découvertes dans Apple macOS. Elles permettent à un attaquant de provoquer une exécution de code arbitraire et une élévation de privilèges.

Official advisory ↗
CERT-FR · French · CERTFR-2021-AVI-063Vulnérabilité dans Sudo

Une vulnérabilité a été découverte dans Sudo. Elle permet à un attaquant de provoquer une élévation de privilèges. Les différents éditeurs de distributions Linux ont déjà publié des correctifs.

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-002344Sensormatic Electronics 製 Illustra に境界条件の判定に関する脆弱性

Sensormatic Electronics 社（Johnson Controls子会社）が提供する Illustra は、監視・防犯カメラシステムです。 Illustra には、境界条件の判定に関する脆弱性（CWE-193、CVE-2021-3156）が存在します。

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2021-001020sudo にヒープベースのバッファオーバーフローの脆弱性

sudo にはコマンドの引数に設定された特殊文字のエスケープ処理の実装に起因した、ヒープベースのバッファオーバーフロー (CWE-122) の脆弱性が存在します。 2021年2月5日時点において、macOS、AIX、Solaris においても影響を受ける可能性があるとの報告がされていますが、発見者による確認は実施されていません。 なお、2021年2月9日に Apple から本件に対応する セキュリティアップデート が公開されました。

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-5263Apple 제품군 보안 업데이트 권고

macOS Big Sur, Catalina, Mojave의 Sudo 명령어에서 발생하는 권한상승 취약점(CVE-2021-3156)[1]

Official advisory ↗
KISA KrCERT/CC · Korean · KNVD-5250Sudo 취약점 보안 업데이트 권고

Sudo 명령어에서 힙 버퍼 오버플로우로 인해 발생하는 권한상승 취약점(CVE-2021-3156) [1]

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
n/a
Fixed
An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 26 Jan 2021 · Last source change 21 Oct 2025, 23:35 UTC · CWE-193 · Off-by-one Error

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2021-26500
Product sourceCISA KEV
Remediation sourceCVE/CNA references
CWE sourceCISA ADP
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Affected versionsThe structured affected or fixed version information changed.
    Before
    n/a: n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    After
    n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    CISA KEV ↗
  2. Affected versionsThe structured affected or fixed version information changed.
    Before
    n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    After
    n/a: n/a · Fixed: An authoritative update reference is available, but the fixed version is not recorded in the structured CVE fields. Check the linked vendor advisory for the applicable release.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Added to CISA KEV
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2021-26500↗CISA KEV record↗Patch or update reference↗Patch or update reference↗Patch or update reference↗Patch or update reference↗CVE authority or vendor reference↗Public exploit reference↗Public exploit reference↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2021-3156 · cve.blacktree.nl