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Full vulnerability report · 2021
CVE-2021-28375High confidence

An issue was discovered in the Linux kernel through 5.11.6

n/a · n/a

7.8HighCVSS 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 10 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-2021-15058

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

An issue was discovered in the Linux kernel through 5.11.6. fastrpc_internal_invoke in drivers/misc/fastrpc.c does not prevent user applications from sending kernel RPC messages, aka CID-20c40794eb85. This is a related issue to CVE-2019-2308.

What

An issue was discovered in the Linux kernel through 5.11.6. fastrpc_internal_invoke in drivers/misc/fastrpc.c does not prevent user applications from sending kernel RPC messages, aka CID-20c40794eb85. This is a related issue to CVE-2019-2308.

Why

The application reaches a protected operation without first confirming that the requester is authorised.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

An issue was discovered in the Linux kernel through 5.11.6. fastrpc_internal_invoke in drivers/misc/fastrpc.c does not prevent user applications from sending kernel RPC messages, aka CID-20c40794eb85. This is a related issue to CVE-2019-2308.

Why

The application reaches a protected operation without first confirming that the requester is authorised.

How

An attacker operating through local access may attempt exploitation with low privileges. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

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 → Missing Authorization → cause the confidentiality, integrity or availability impact described by the vendor
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-862

CWE-862: Missing Authorization. The product does not perform an authorization check when an actor attempts to access a resource or perform an action.

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.
CWE-862
A

Official authority intelligence

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

CERT-FR · French · CERTFR-2021-AVI-590Multiples vulnérabilités dans Google Android

.cve.org/CVERecord?id=CVE-2021-1919 Référence CVE CVE-2021-1920 https://www.cve.org/CVERecord?id=CVE-2021-1920 Référence CVE CVE-2021-1929 https://www.cve.org/CVERecord?id=CVE-2021-1929 Référence CVE CVE-2021-1930 https://www.cve.org/CVERecord?id=CVE-2021-1930 Référence CVE CVE-2021-1939 https://www.cve.org/CVERecord?id=CVE-2021-1939 Référence CVE CVE-2021-1947 https://www.cve.org/CVERecord?id=CVE-2021-1947 Référence CVE CVE-2021-1972 https://www.cve.org/CVERecord?id=CVE-2021-1972 Référence CVE CVE-2021-1976 https://www.cve.org/CVERecord?id=CVE-2021-1976 Référence CVE CVE-2021-1978 https://www.cve.org/CVERecord?id=CVE-2021-1978 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-30260 https://www.cve.org/CVERecord?id=CVE-2021-30260 Référence CVE CVE-2021-30261 https://www.cve.org/CVERecord?id=CVE-2021-30261 Référence CVE CVE-2021-3347 https://www.cve.org/CVERecord?id=CVE-2021-3347 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 syst

Official advisory
CERT-FR · French · CERTFR-2021-AVI-469Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-36311 Référence CVE CVE-2020-36312 https://www.cve.org/CVERecord?id=CVE-2020-36312 Référence CVE CVE-2020-36322 https://www.cve.org/CVERecord?id=CVE-2020-36322 Référence CVE CVE-2021-20268 https://www.cve.org/CVERecord?id=CVE-2021-20268 Référence CVE CVE-2021-23134 https://www.cve.org/CVERecord?id=CVE-2021-23134 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-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-28660 https://www.cve.org/CVERecord?id=CVE-2021-28660 Référence CVE CVE-2021-28688 https://www.cve.org/CVERecord?id=CVE-2021-28688 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-28952 https://www.cve.org/CVERecord?id=CVE-2021-28952 Référence CVE CVE-2021-28964 https://www.cve.org/CVERecord?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-393Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu. Elles permettent à un attaquant de provoquer un déni de service et une élévation de privilèges.

Official advisory
CERT-FR · French · CERTFR-2021-AVI-392Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-36310 Référence CVE CVE-2020-36311 https://www.cve.org/CVERecord?id=CVE-2020-36311 Référence CVE CVE-2020-36312 https://www.cve.org/CVERecord?id=CVE-2020-36312 Référence CVE CVE-2020-36322 https://www.cve.org/CVERecord?id=CVE-2020-36322 Référence CVE CVE-2021-20219 https://www.cve.org/CVERecord?id=CVE-2021-20219 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-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-28660 https://www.cve.org/CVERecord?id=CVE-2021-28660 Référence CVE CVE-2021-28688 https://www.cve.org/CVERecord?id=CVE-2021-28688 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-28964 https://www.cve.org/CVERecord?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=CVE-2021-29154 Référence CVE CVE-2021-29155 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-372Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2020-25639 Référence CVE CVE-2020-25670 https://www.cve.org/CVERecord?id=CVE-2020-25670 Référence CVE CVE-2020-25671 https://www.cve.org/CVERecord?id=CVE-2020-25671 Référence CVE CVE-2020-25672 https://www.cve.org/CVERecord?id=CVE-2020-25672 Référence CVE CVE-2020-35519 https://www.cve.org/CVERecord?id=CVE-2020-35519 Référence CVE CVE-2021-20292 https://www.cve.org/CVERecord?id=CVE-2021-20292 Référence CVE CVE-2021-26930 https://www.cve.org/CVERecord?id=CVE-2021-26930 Référence CVE CVE-2021-26931 https://www.cve.org/CVERecord?id=CVE-2021-26931 Référence CVE CVE-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-28660 https://www.cve.org/CVERecord?id=CVE-2021-28660 Référence CVE CVE-2021-28688 https://www.cve.org/CVERecord?id=CVE-2021-28688 Référence CVE CVE-2021-28951 https://www.cve.org/CVERecord?id=CVE-2021-28951 Référence CVE CVE-2021-28952 https://www.cve.org/CVERecord?id=CVE-2021-28952 Référence CVE CVE-2021-28964 https://www.cve.org/CVERecord?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-284Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-36310 Référence CVE CVE-2020-36311 https://www.cve.org/CVERecord?id=CVE-2020-36311 Référence CVE CVE-2020-36312 https://www.cve.org/CVERecord?id=CVE-2020-36312 Référence CVE CVE-2020-36322 https://www.cve.org/CVERecord?id=CVE-2020-36322 Référence CVE CVE-2021-20219 https://www.cve.org/CVERecord?id=CVE-2021-20219 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-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-28660 https://www.cve.org/CVERecord?id=CVE-2021-28660 Référence CVE CVE-2021-28688 https://www.cve.org/CVERecord?id=CVE-2021-28688 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-28964 https://www.cve.org/CVERecord?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=CVE-2021-29154 Référence CVE CVE-2021-29264 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-278Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-36312 Référence CVE CVE-2021-20219 https://www.cve.org/CVERecord?id=CVE-2021-20219 Référence CVE CVE-2021-26930 https://www.cve.org/CVERecord?id=CVE-2021-26930 Référence CVE CVE-2021-26931 https://www.cve.org/CVERecord?id=CVE-2021-26931 Référence CVE CVE-2021-26932 https://www.cve.org/CVERecord?id=CVE-2021-26932 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-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-28660 https://www.cve.org/CVERecord?id=CVE-2021-28660 Référence CVE CVE-2021-28688 https://www.cve.org/CVERecord?id=CVE-2021-28688 Référence CVE CVE-2021-28950 https://www.cve.org/CVERecord?id=CVE-2021-28950 Référence CVE CVE-2021-28964 https://www.cve.org/CVERecord?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29154 https://www.cve.org/CVERecord?id=CVE-2021-29154 Référence CVE CVE-2021-29264 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-264Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-29374 Référence CVE CVE-2020-35519 https://www.cve.org/CVERecord?id=CVE-2020-35519 Référence CVE CVE-2021-26930 https://www.cve.org/CVERecord?id=CVE-2021-26930 Référence CVE CVE-2021-26931 https://www.cve.org/CVERecord?id=CVE-2021-26931 Référence CVE CVE-2021-26932 https://www.cve.org/CVERecord?id=CVE-2021-26932 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-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 Référence CVE CVE-2021-28660 https://www.cve.org/CVERecord?id=CVE-2021-28660 Référence CVE CVE-2021-28688 https://www.cve.org/CVERecord?id=CVE-2021-28688 Référence CVE CVE-2021-28964 https://www.cve.org/CVERecord?id=CVE-2021-28964 Référence CVE CVE-2021-28971 https://www.cve.org/CVERecord?id=CVE-2021-28971 Référence CVE CVE-2021-28972 https://www.cve.org/CVERecord?id=CVE-2021-28972 Référence CVE CVE-2021-29264 https://www.cve.org/CVERecord?id=CVE-2021-29264 Référence CVE CVE-2021-29265 https://www.cve.org/CVERecord?id=CVE-2021-29265 Référence CVE CVE-2021-29647 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-265Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2020-27830 Référence CVE CVE-2020-36158 https://www.cve.org/CVERecord?id=CVE-2020-36158 Référence CVE CVE-2021-20194 https://www.cve.org/CVERecord?id=CVE-2021-20194 Référence CVE CVE-2021-20239 https://www.cve.org/CVERecord?id=CVE-2021-20239 Référence CVE CVE-2021-20261 https://www.cve.org/CVERecord?id=CVE-2021-20261 Référence CVE CVE-2021-20268 https://www.cve.org/CVERecord?id=CVE-2021-20268 Référence CVE CVE-2021-26930 https://www.cve.org/CVERecord?id=CVE-2021-26930 Référence CVE CVE-2021-26931 https://www.cve.org/CVERecord?id=CVE-2021-26931 Référence CVE CVE-2021-28038 https://www.cve.org/CVERecord?id=CVE-2021-28038 Référence CVE CVE-2021-28375 https://www.cve.org/CVERecord?id=CVE-2021-28375 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-2021-3178 https://www.cve.org/CVERecord?id=CVE-2021-3178 Référence CVE CVE-2021-3347 https://www.cve.org/CVERecord?id=CVE-2021-3347 Référence CVE CVE-2021-3348 https://www.cve.org/CVERecord?id=CVE-2021-3348 Référence CVE CVE-2021-3411 https://www.cve.org/CVERecord?id=CVE-2021-3411 Gestion détaillée du document le 15 avril 2021 Version initiale Alertes Avis Bulletins d’actualités Mentions légales Conditions générales À propos

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 15 Mar 2021 · Last source change 3 Aug 2024, 21:40 UTC · CWE-862 · Missing Authorization

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-2021-15058
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
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-2021-28375 · cve.blacktree.nl