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Full vulnerability report · 2022
CVE-2021-4154High confidence

A use-after-free flaw was found in cgroup1_parse_param in kernel/cgroup/cgroup-v1.c in the Linux kernel's cgroup v1 parser

n/a · kernel

8.8HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

1 package state
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.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · standard archivelinux-raspi-realtimeAffected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.Not published in this feedCanonical record ↗Source updated 8 Sept 2026
Optional official sources

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

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

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-2021-34022

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

A use-after-free flaw was found in cgroup1_parse_param in kernel/cgroup/cgroup-v1.c in the Linux kernel's cgroup v1 parser. A local attacker with a user privilege could cause a privilege escalation by exploiting the fsconfig syscall parameter leading to a container breakout and a denial of service on the system.

What

A use-after-free flaw was found in cgroup1_parse_param in kernel/cgroup/cgroup-v1.c in the Linux kernel's cgroup v1 parser. A local attacker with a user privilege could cause a privilege escalation by exploiting the fsconfig syscall parameter leading to a container breakout and a denial of service on the system.

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

How

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

What

A use-after-free flaw was found in cgroup1_parse_param in kernel/cgroup/cgroup-v1.c in the Linux kernel's cgroup v1 parser. A local attacker with a user privilege could cause a privilege escalation by exploiting the fsconfig syscall parameter leading to a container breakout and a denial of service on the system.

Why

The program can continue using memory after it has been released, producing unsafe and attacker-influenceable behaviour.

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.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
local access → Use After Free → 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
Changed: exploitation can affect a different security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-416

CWE-416: Use After Free. The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory belongs to the code that operates on the new pointer.

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:C/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.SChangedScope: The attack can affect a component governed by a different security 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 escalationDenial of serviceCWE-416
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2022-0515IBM Spectrum Protect: Mehrere Schwachstellen

Ein entfernter, anonymer, authentisierter oder lokaler Angreifer kann mehrere Schwachstellen in IBM Spectrum Protect ausnutzen, um einen Denial-of-Service-Zustand herbeizuführen, Sicherheitsmaßnahmen zu umgehen, vertrauliche Informationen offenzulegen, beliebigen Code auszuführen, seine Rechte zu erweitern oder beliebigen Code mit Root-Rechten auszuführen.

Official advisory
BSI · German · WID-SEC-W-2022-0137Android Patchday Juni 2022

Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Google Android ausnutzen, um seine Privilegien zu erhöhen, vertrauliche Informationen offenzulegen, beliebigen Code auszuführen und einen Denial-of-Service-Zustand auszulösen.

Official advisory
CERT-FR · French · CERTFR-2022-AVI-591Multiples vulnérabilités dans les produits IBM

.org/CVERecord?id=CVE-2021-3573 Référence CVE CVE-2021-3635 https://www.cve.org/CVERecord?id=CVE-2021-3635 Référence CVE CVE-2021-3669 https://www.cve.org/CVERecord?id=CVE-2021-3669 Référence CVE CVE-2021-3764 https://www.cve.org/CVERecord?id=CVE-2021-3764 Référence CVE CVE-2021-38201 https://www.cve.org/CVERecord?id=CVE-2021-38201 Référence CVE CVE-2021-4002 https://www.cve.org/CVERecord?id=CVE-2021-4002 Référence CVE CVE-2021-4028 https://www.cve.org/CVERecord?id=CVE-2021-4028 Référence CVE CVE-2021-4083 https://www.cve.org/CVERecord?id=CVE-2021-4083 Référence CVE CVE-2021-41190 https://www.cve.org/CVERecord?id=CVE-2021-41190 Référence CVE CVE-2021-4154 https://www.cve.org/CVERecord?id=CVE-2021-4154 Référence CVE CVE-2021-4155 https://www.cve.org/CVERecord?id=CVE-2021-4155 Référence CVE CVE-2021-4157 https://www.cve.org/CVERecord?id=CVE-2021-4157 Référence CVE CVE-2021-41864 https://www.cve.org/CVERecord?id=CVE-2021-41864 Référence CVE CVE-2021-4197 https://www.cve.org/CVERecord?id=CVE-2021-4197 Référence CVE CVE-2021-4203 https://www.cve.org/CVERecord?id=CVE-2021-4203 Référence CVE CVE-2021-42248 https://www.cve.org/CVERecord?id=CVE-2021-42248 Référence CVE CVE-2021-42836 https://www.cve.org/CVERecord?id=CVE-2021-42836 Référence CVE CVE-2021-43565 https://www.cve.org/CVERecord?id=CVE-2021-

Official advisory
CERT-FR · French · CERTFR-2022-AVI-524Multiples vulnérabilités dans Google Android

alité des données. Solution Se référer au bulletin de sécurité de l'éditeur pour l'obtention des correctifs (cf. section Documentation). Documentation Bulletin de sécurité Google du 06 juin 2022 https://source.android.com/security/bulletin/2022-06-01 Référence CVE CVE-2021-35083 https://www.cve.org/CVERecord?id=CVE-2021-35083 Référence CVE CVE-2021-35102 https://www.cve.org/CVERecord?id=CVE-2021-35102 Référence CVE CVE-2021-35111 https://www.cve.org/CVERecord?id=CVE-2021-35111 Référence CVE CVE-2021-39624 https://www.cve.org/CVERecord?id=CVE-2021-39624 Référence CVE CVE-2021-39691 https://www.cve.org/CVERecord?id=CVE-2021-39691 Référence CVE CVE-2021-4154 https://www.cve.org/CVERecord?id=CVE-2021-4154 Référence CVE CVE-2022-20006 https://www.cve.org/CVERecord?id=CVE-2022-20006 Référence CVE CVE-2022-20123 https://www.cve.org/CVERecord?id=CVE-2022-20123 Référence CVE CVE-2022-20124 https://www.cve.org/CVERecord?id=CVE-2022-20124 Référence CVE CVE-2022-20125 https://www.cve.org/CVERecord?id=CVE-2022-20125 Référence CVE CVE-2022-20126 https://www.cve.org/CVERecord?id=CVE-2022-20126 Référence CVE CVE-2022-20127 https://www.cve.org/CVERecord?id=CVE-2022-20127 Référence CVE CVE-2022-20129 https://www.cve.org/CVERecord?id=CVE-2022-20129 Référence CVE CVE-2022-20130 https://www.cve.org/CVERecord?id=C

Official advisory
CERT-FR · French · CERTFR-2022-AVI-238Multiples vulnérabilités dans le noyau Linux de Red Hat

De multiples vulnérabilités ont été découvertes dans le noyau Linux de Red Hat. Certaines d'entre elles permettent à un attaquant de provoquer un déni de service, un contournement de la politique de sécurité et une atteinte à l'intégrité des données.

Official advisory
CERT-FR · French · CERTFR-2022-AVI-108Multiples vulnérabilités dans le noyau Linux de SUSE

g/CVERecord?id=CVE-2020-25671 Référence CVE CVE-2020-25672 https://www.cve.org/CVERecord?id=CVE-2020-25672 Référence CVE CVE-2020-25673 https://www.cve.org/CVERecord?id=CVE-2020-25673 Référence CVE CVE-2020-3702 https://www.cve.org/CVERecord?id=CVE-2020-3702 Référence CVE CVE-2021-23134 https://www.cve.org/CVERecord?id=CVE-2021-23134 Référence CVE CVE-2021-4028 https://www.cve.org/CVERecord?id=CVE-2021-4028 Référence CVE CVE-2021-4083 https://www.cve.org/CVERecord?id=CVE-2021-4083 Référence CVE CVE-2021-4135 https://www.cve.org/CVERecord?id=CVE-2021-4135 Référence CVE CVE-2021-4149 https://www.cve.org/CVERecord?id=CVE-2021-4149 Référence CVE CVE-2021-4154 https://www.cve.org/CVERecord?id=CVE-2021-4154 Référence CVE CVE-2021-4197 https://www.cve.org/CVERecord?id=CVE-2021-4197 Référence CVE CVE-2021-4202 https://www.cve.org/CVERecord?id=CVE-2021-4202 Référence CVE CVE-2021-42739 https://www.cve.org/CVERecord?id=CVE-2021-42739 Référence CVE CVE-2021-44733 https://www.cve.org/CVERecord?id=CVE-2021-44733 Référence CVE CVE-2021-45485 https://www.cve.org/CVERecord?id=CVE-2021-45485 Référence CVE CVE-2021-45486 https://www.cve.org/CVERecord?id=CVE-2021-45486 Référence CVE CVE-2021-46283 https://www.cve.org/CVERecord?id=CVE-2021-46283 Référence CVE CVE-2022-0185 https://www.cve.org/CVERecord?id=CVE-20

Official advisory
CERT-FR · French · CERTFR-2022-AVI-100Multiples vulnérabilités dans le noyau Linux de SUSE

De multiples vulnérabilités ont été découvertes dans le noyau Linux de SUSE. Certaines d'entre elles permettent à un attaquant de provoquer un problème de sécurité non spécifié par l'éditeur, un déni de service et une atteinte à l'intégrité des données.

Official advisory
CERT-FR · French · CERTFR-2022-AVI-064Multiples vulnérabilités dans le noyau Linux de Red Hat

De multiples vulnérabilités ont été découvertes dans le noyau Linux de Red Hat. Elles permettent à un attaquant de provoquer un déni de service, une atteinte à la confidentialité des données et une élévation de privilèges.

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
Fixed in kernel 5.14 rc2
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 4 Feb 2022 · Last source change 3 Aug 2024, 17:16 UTC · CWE-416 · Use After Free

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-2021-34022
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD modified after enrichment

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

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
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-2021-4154 · cve.blacktree.nl