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Full vulnerability report · 2020
CVE-2020-28974High confidence

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095

n/a · n/a

5.0MediumCVSS 3.1
Recommended action
Within 7 days

Medium technical severity with public exploit material referenced by a structured source; 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 9 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-2020-21358

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

Medium technical severity with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Patch available
01

What, why and how

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height.

What

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through physical access may attempt exploitation with elevated privileges. If successful, the issue may disrupt the affected service.

What

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height.

Why

The product reads data past the end, or before the beginning, of the intended buffer.

How

An attacker operating through physical access may attempt exploitation with elevated privileges. If successful, the issue may disrupt the affected service.

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.
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
physical access → Out-of-bounds Read → disrupt the affected service
Attack surface
Physical
Privileges required
High: elevated access 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-125

CWE-125: Out-of-bounds Read. The product reads data past the end, or before the beginning, of the intended buffer.

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

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

AVPhysicalAttack vector: The attacker needs physical access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRHighPrivileges required: The attacker needs elevated or administrative privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CLowConfidentiality impact: A successful attack can cause a limited loss.ILowIntegrity impact: A successful attack can cause a limited loss.AHighAvailability impact: A successful attack can cause a major loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
Denial of serviceCWE-125Public exploit reference
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-149Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2020-27675 Référence CVE CVE-2020-27777 https://www.cve.org/CVERecord?id=CVE-2020-27777 Référence CVE CVE-2020-27815 https://www.cve.org/CVERecord?id=CVE-2020-27815 Référence CVE CVE-2020-27830 https://www.cve.org/CVERecord?id=CVE-2020-27830 Référence CVE CVE-2020-27835 https://www.cve.org/CVERecord?id=CVE-2020-27835 Référence CVE CVE-2020-28374 https://www.cve.org/CVERecord?id=CVE-2020-28374 Référence CVE CVE-2020-28588 https://www.cve.org/CVERecord?id=CVE-2020-28588 Référence CVE CVE-2020-28915 https://www.cve.org/CVERecord?id=CVE-2020-28915 Référence CVE CVE-2020-28941 https://www.cve.org/CVERecord?id=CVE-2020-28941 Référence CVE CVE-2020-28974 https://www.cve.org/CVERecord?id=CVE-2020-28974 Référence CVE CVE-2020-29368 https://www.cve.org/CVERecord?id=CVE-2020-29368 Référence CVE CVE-2020-29369 https://www.cve.org/CVERecord?id=CVE-2020-29369 Référence CVE CVE-2020-29371 https://www.cve.org/CVERecord?id=CVE-2020-29371 Référence CVE CVE-2020-29374 https://www.cve.org/CVERecord?id=CVE-2020-29374 Référence CVE CVE-2020-29568 https://www.cve.org/CVERecord?id=CVE-2020-29568 Référence CVE CVE-2020-29569 https://www.cve.org/CVERecord?id=CVE-2020-29569 Référence CVE CVE-2020-29660 https://www.cve.org/CVERecord?id=CVE-2020-29660 Référence CVE CVE-2020-29661 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2021-AVI-125Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-25285 Référence CVE CVE-2020-25643 https://www.cve.org/CVERecord?id=CVE-2020-25643 Référence CVE CVE-2020-25656 https://www.cve.org/CVERecord?id=CVE-2020-25656 Référence CVE CVE-2020-25668 https://www.cve.org/CVERecord?id=CVE-2020-25668 Référence CVE CVE-2020-25669 https://www.cve.org/CVERecord?id=CVE-2020-25669 Référence CVE CVE-2020-27068 https://www.cve.org/CVERecord?id=CVE-2020-27068 Référence CVE CVE-2020-27777 https://www.cve.org/CVERecord?id=CVE-2020-27777 Référence CVE CVE-2020-27786 https://www.cve.org/CVERecord?id=CVE-2020-27786 Référence CVE CVE-2020-28915 https://www.cve.org/CVERecord?id=CVE-2020-28915 Référence CVE CVE-2020-28974 https://www.cve.org/CVERecord?id=CVE-2020-28974 Référence CVE CVE-2020-29660 https://www.cve.org/CVERecord?id=CVE-2020-29660 Référence CVE CVE-2020-29661 https://www.cve.org/CVERecord?id=CVE-2020-29661 Référence CVE CVE-2020-36158 https://www.cve.org/CVERecord?id=CVE-2020-36158 Référence CVE CVE-2020-4788 https://www.cve.org/CVERecord?id=CVE-2020-4788 Référence CVE CVE-2021-3347 https://www.cve.org/CVERecord?id=CVE-2021-3347 Gestion détaillée du document le 17 février 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

Official advisory
CERT-FR · French · CERTFR-2021-AVI-120Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-25669 Référence CVE CVE-2020-27068 https://www.cve.org/CVERecord?id=CVE-2020-27068 Référence CVE CVE-2020-27673 https://www.cve.org/CVERecord?id=CVE-2020-27673 Référence CVE CVE-2020-27777 https://www.cve.org/CVERecord?id=CVE-2020-27777 Référence CVE CVE-2020-27786 https://www.cve.org/CVERecord?id=CVE-2020-27786 Référence CVE CVE-2020-27825 https://www.cve.org/CVERecord?id=CVE-2020-27825 Référence CVE CVE-2020-27835 https://www.cve.org/CVERecord?id=CVE-2020-27835 Référence CVE CVE-2020-28374 https://www.cve.org/CVERecord?id=CVE-2020-28374 Référence CVE CVE-2020-28915 https://www.cve.org/CVERecord?id=CVE-2020-28915 Référence CVE CVE-2020-28974 https://www.cve.org/CVERecord?id=CVE-2020-28974 Référence CVE CVE-2020-29371 https://www.cve.org/CVERecord?id=CVE-2020-29371 Référence CVE CVE-2020-29568 https://www.cve.org/CVERecord?id=CVE-2020-29568 Référence CVE CVE-2020-29569 https://www.cve.org/CVERecord?id=CVE-2020-29569 Référence CVE CVE-2020-29660 https://www.cve.org/CVERecord?id=CVE-2020-29660 Référence CVE CVE-2020-29661 https://www.cve.org/CVERecord?id=CVE-2020-29661 Référence CVE CVE-2020-36158 https://www.cve.org/CVERecord?id=CVE-2020-36158 Référence CVE CVE-2020-4788 https://www.cve.org/CVERecord?id=CVE-2020-4788 Référence CVE CVE-2021-0342 https://www.cve.org/CVERecord?id=CVE

Official advisory
CERT-FR · French · CERTFR-2021-AVI-012Vulnérabilité dans le noyau Linux d'Ubuntu

Une vulnérabilité a été découverte dans le noyau Linux d'Ubuntu. Elle permet à un attaquant de provoquer un déni de service et une atteinte à la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2021-AVI-006Multiples vulnérabilités dans le noyau Linux d'Ubuntu

De multiples vulnérabilités ont été découvertes dans le noyau Linux d'Ubuntu. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire, un déni de service et un contournement de la politique de sécurité.

Official advisory
CERT-FR · French · CERTFR-2020-AVI-834Multiples vulnérabilités dans le noyau Linux de Debian LTS

De multiples vulnérabilités ont été découvertes dans le noyau Linux de Debian LTS. 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-2020-AVI-837Multiples 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 la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2020-AVI-820Multiples 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-2020-AVI-811Multiples 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 la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2020-AVI-776Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2020-25285 Référence CVE CVE-2020-25641 https://www.cve.org/CVERecord?id=CVE-2020-25641 Référence CVE CVE-2020-25643 https://www.cve.org/CVERecord?id=CVE-2020-25643 Référence CVE CVE-2020-25645 https://www.cve.org/CVERecord?id=CVE-2020-25645 Référence CVE CVE-2020-25656 https://www.cve.org/CVERecord?id=CVE-2020-25656 Référence CVE CVE-2020-25668 https://www.cve.org/CVERecord?id=CVE-2020-25668 Référence CVE CVE-2020-25704 https://www.cve.org/CVERecord?id=CVE-2020-25704 Référence CVE CVE-2020-25705 https://www.cve.org/CVERecord?id=CVE-2020-25705 Référence CVE CVE-2020-26088 https://www.cve.org/CVERecord?id=CVE-2020-26088 Référence CVE CVE-2020-28974 https://www.cve.org/CVERecord?id=CVE-2020-28974 Référence CVE CVE-2020-8694 https://www.cve.org/CVERecord?id=CVE-2020-8694 Gestion détaillée du document le 26 novembre 2020 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
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 20 Nov 2020 · Last source change 4 Aug 2024, 16:48 UTC · CWE-125 · Out-of-bounds Read

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-2020-21358
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-2020-28974 · cve.blacktree.nl