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Full vulnerability report · 2023
CVE-2023-1872High confidence

Use-after-free in Linux kernel's io_uring subsystem

Linux · Linux Kernel

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 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-2023-24074

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 vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation. The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered. We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.

What

A use-after-free vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation. The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered. We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.

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 vulnerability in the Linux Kernel io_uring system can be exploited to achieve local privilege escalation. The io_file_get_fixed function lacks the presence of ctx->uring_lock which can lead to a Use-After-Free vulnerability due a race condition with fixed files getting unregistered. We recommend upgrading past commit da24142b1ef9fd5d36b76e36bab328a5b27523e8.

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
Unchanged: impact remains within the vulnerable component's 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: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-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-2023-0956Linux Kernel: Schwachstelle ermöglicht Privilegieneskalation

Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um seine Privilegien zu erhöhen.

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0275Multiples 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, une élévation de privilèges et une atteinte à la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0488Multiples vulnérabilités dans le noyau Linux d'Ubuntu

.cve.org/CVERecord?id=CVE-2023-1076 Référence CVE CVE-2023-1077 https://www.cve.org/CVERecord?id=CVE-2023-1077 Référence CVE CVE-2023-1079 https://www.cve.org/CVERecord?id=CVE-2023-1079 Référence CVE CVE-2023-1380 https://www.cve.org/CVERecord?id=CVE-2023-1380 Référence CVE CVE-2023-1583 https://www.cve.org/CVERecord?id=CVE-2023-1583 Référence CVE CVE-2023-1611 https://www.cve.org/CVERecord?id=CVE-2023-1611 Référence CVE CVE-2023-1670 https://www.cve.org/CVERecord?id=CVE-2023-1670 Référence CVE CVE-2023-1855 https://www.cve.org/CVERecord?id=CVE-2023-1855 Référence CVE CVE-2023-1859 https://www.cve.org/CVERecord?id=CVE-2023-1859 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-1989 https://www.cve.org/CVERecord?id=CVE-2023-1989 Référence CVE CVE-2023-1990 https://www.cve.org/CVERecord?id=CVE-2023-1990 Référence CVE CVE-2023-1998 https://www.cve.org/CVERecord?id=CVE-2023-1998 Référence CVE CVE-2023-2002 https://www.cve.org/CVERecord?id=CVE-2023-2002 Référence CVE CVE-2023-2156 https://www.cve.org/CVERecord?id=CVE-2023-2156 Référence CVE CVE-2023-2194 https://www.cve.org/CVERecord?id=CVE-2023-2194 Référence CVE CVE-2023-2235 https://www.cve.org/CVERecord?id=CVE-2023-2235 Référence CVE CVE-2023-2269 https://www.cve.org/CVERecord?id=CVE-2023-2269 Ré

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0447Multiples vulnérabilités dans le noyau Linux de SUSE

.org/CVERecord?id=CVE-2022-3523 Référence CVE CVE-2022-36280 https://www.cve.org/CVERecord?id=CVE-2022-36280 Référence CVE CVE-2022-38096 https://www.cve.org/CVERecord?id=CVE-2022-38096 Référence CVE CVE-2023-0045 https://www.cve.org/CVERecord?id=CVE-2023-0045 Référence CVE CVE-2023-0386 https://www.cve.org/CVERecord?id=CVE-2023-0386 Référence CVE CVE-2023-0461 https://www.cve.org/CVERecord?id=CVE-2023-0461 Référence CVE CVE-2023-0597 https://www.cve.org/CVERecord?id=CVE-2023-0597 Référence CVE CVE-2023-1118 https://www.cve.org/CVERecord?id=CVE-2023-1118 Référence CVE CVE-2023-1281 https://www.cve.org/CVERecord?id=CVE-2023-1281 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-1989 https://www.cve.org/CVERecord?id=CVE-2023-1989 Référence CVE CVE-2023-2162 https://www.cve.org/CVERecord?id=CVE-2023-2162 Référence CVE CVE-2023-22995 https://www.cve.org/CVERecord?id=CVE-2023-22995 Référence CVE CVE-2023-22998 https://www.cve.org/CVERecord?id=CVE-2023-22998 Référence CVE CVE-2023-23000 https://www.cve.org/CVERecord?id=CVE-2023-23000 Référence CVE CVE-2023-23004 https://www.cve.org/CVERecord?id=CVE-2023-23004 Référence CVE CVE-2023-23454 https://www.cve.org/CVERecord?id=CVE-2023-23454 Référence CVE CVE-2023-23559 https://www.cve.org/CVERecord?id=CVE-2

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0429Multiples vulnérabilités dans le noyau Linux d'Ubuntu

.cve.org/CVERecord?id=CVE-2023-1075 Référence CVE CVE-2023-1078 https://www.cve.org/CVERecord?id=CVE-2023-1078 Référence CVE CVE-2023-1118 https://www.cve.org/CVERecord?id=CVE-2023-1118 Référence CVE CVE-2023-1281 https://www.cve.org/CVERecord?id=CVE-2023-1281 Référence CVE CVE-2023-1380 https://www.cve.org/CVERecord?id=CVE-2023-1380 Référence CVE CVE-2023-1513 https://www.cve.org/CVERecord?id=CVE-2023-1513 Référence CVE CVE-2023-1652 https://www.cve.org/CVERecord?id=CVE-2023-1652 Référence CVE CVE-2023-1670 https://www.cve.org/CVERecord?id=CVE-2023-1670 Référence CVE CVE-2023-1829 https://www.cve.org/CVERecord?id=CVE-2023-1829 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-20938 https://www.cve.org/CVERecord?id=CVE-2023-20938 Référence CVE CVE-2023-21102 https://www.cve.org/CVERecord?id=CVE-2023-21102 Référence CVE CVE-2023-2162 https://www.cve.org/CVERecord?id=CVE-2023-2162 Référence CVE CVE-2023-2612 https://www.cve.org/CVERecord?id=CVE-2023-2612 Référence CVE CVE-2023-26545 https://www.cve.org/CVERecord?id=CVE-2023-26545 Référence CVE CVE-2023-26606 https://www.cve.org/CVERecord?id=CVE-2023-26606 Référence CVE CVE-2023-30456 https://www.cve.org/CVERecord?id=CVE-2023-30456 Référence CVE CVE-2023-31436 https://www.cve.org/CVERecord?id=CVE-2

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0411Multiples vulnérabilités dans le noyau Linux d'Ubuntu

.cve.org/CVERecord?id=CVE-2023-1073 Référence CVE CVE-2023-1074 https://www.cve.org/CVERecord?id=CVE-2023-1074 Référence CVE CVE-2023-1075 https://www.cve.org/CVERecord?id=CVE-2023-1075 Référence CVE CVE-2023-1078 https://www.cve.org/CVERecord?id=CVE-2023-1078 Référence CVE CVE-2023-1118 https://www.cve.org/CVERecord?id=CVE-2023-1118 Référence CVE CVE-2023-1281 https://www.cve.org/CVERecord?id=CVE-2023-1281 Référence CVE CVE-2023-1513 https://www.cve.org/CVERecord?id=CVE-2023-1513 Référence CVE CVE-2023-1652 https://www.cve.org/CVERecord?id=CVE-2023-1652 Référence CVE CVE-2023-1829 https://www.cve.org/CVERecord?id=CVE-2023-1829 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-21102 https://www.cve.org/CVERecord?id=CVE-2023-21102 Référence CVE CVE-2023-21106 https://www.cve.org/CVERecord?id=CVE-2023-21106 Référence CVE CVE-2023-2162 https://www.cve.org/CVERecord?id=CVE-2023-2162 Référence CVE CVE-2023-23454 https://www.cve.org/CVERecord?id=CVE-2023-23454 Référence CVE CVE-2023-23455 https://www.cve.org/CVERecord?id=CVE-2023-23455 Référence CVE CVE-2023-26544 https://www.cve.org/CVERecord?id=CVE-2023-26544 Référence CVE CVE-2023-26545 https://www.cve.org/CVERecord?id=CVE-2023-26545 Référence CVE CVE-2023-32269 https://www.cve.org/CVERecord?id=CVE

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0392Multiples vulnérabilités dans le noyau Linux de DebianLTS

.cve.org/CVERecord?id=CVE-2023-1079 Référence CVE CVE-2023-1118 https://www.cve.org/CVERecord?id=CVE-2023-1118 Référence CVE CVE-2023-1281 https://www.cve.org/CVERecord?id=CVE-2023-1281 Référence CVE CVE-2023-1513 https://www.cve.org/CVERecord?id=CVE-2023-1513 Référence CVE CVE-2023-1611 https://www.cve.org/CVERecord?id=CVE-2023-1611 Référence CVE CVE-2023-1670 https://www.cve.org/CVERecord?id=CVE-2023-1670 Référence CVE CVE-2023-1829 https://www.cve.org/CVERecord?id=CVE-2023-1829 Référence CVE CVE-2023-1855 https://www.cve.org/CVERecord?id=CVE-2023-1855 Référence CVE CVE-2023-1859 https://www.cve.org/CVERecord?id=CVE-2023-1859 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-1989 https://www.cve.org/CVERecord?id=CVE-2023-1989 Référence CVE CVE-2023-1990 https://www.cve.org/CVERecord?id=CVE-2023-1990 Référence CVE CVE-2023-1998 https://www.cve.org/CVERecord?id=CVE-2023-1998 Référence CVE CVE-2023-2162 https://www.cve.org/CVERecord?id=CVE-2023-2162 Référence CVE CVE-2023-2194 https://www.cve.org/CVERecord?id=CVE-2023-2194 Référence CVE CVE-2023-22998 https://www.cve.org/CVERecord?id=CVE-2023-22998 Référence CVE CVE-2023-23004 https://www.cve.org/CVERecord?id=CVE-2023-23004 Référence CVE CVE-2023-23454 https://www.cve.org/CVERecord?id=CVE-2023-23

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0382Multiples vulnérabilités dans le noyau Linux de SUSE

cement/2023/suse-su-20232163-1/ Référence CVE CVE-2020-36691 https://www.cve.org/CVERecord?id=CVE-2020-36691 Référence CVE CVE-2022-2196 https://www.cve.org/CVERecord?id=CVE-2022-2196 Référence CVE CVE-2022-43945 https://www.cve.org/CVERecord?id=CVE-2022-43945 Référence CVE CVE-2023-0386 https://www.cve.org/CVERecord?id=CVE-2023-0386 Référence CVE CVE-2023-1611 https://www.cve.org/CVERecord?id=CVE-2023-1611 Référence CVE CVE-2023-1670 https://www.cve.org/CVERecord?id=CVE-2023-1670 Référence CVE CVE-2023-1838 https://www.cve.org/CVERecord?id=CVE-2023-1838 Référence CVE CVE-2023-1855 https://www.cve.org/CVERecord?id=CVE-2023-1855 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-1989 https://www.cve.org/CVERecord?id=CVE-2023-1989 Référence CVE CVE-2023-1990 https://www.cve.org/CVERecord?id=CVE-2023-1990 Référence CVE CVE-2023-1998 https://www.cve.org/CVERecord?id=CVE-2023-1998 Référence CVE CVE-2023-2008 https://www.cve.org/CVERecord?id=CVE-2023-2008 Référence CVE CVE-2023-2019 https://www.cve.org/CVERecord?id=CVE-2023-2019 Référence CVE CVE-2023-2124 https://www.cve.org/CVERecord?id=CVE-2023-2124 Référence CVE CVE-2023-2162 https://www.cve.org/CVERecord?id=CVE-2023-2162 Référence CVE CVE-2023-2176 https://www.cve.org/CVERecord?id=CVE-2023-2176 Ré

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0381Multiples vulnérabilités dans le noyau Linux d'Ubuntu

.cve.org/CVERecord?id=CVE-2023-0386 Référence CVE CVE-2023-0394 https://www.cve.org/CVERecord?id=CVE-2023-0394 Référence CVE CVE-2023-0468 https://www.cve.org/CVERecord?id=CVE-2023-0468 Référence CVE CVE-2023-1073 https://www.cve.org/CVERecord?id=CVE-2023-1073 Référence CVE CVE-2023-1074 https://www.cve.org/CVERecord?id=CVE-2023-1074 Référence CVE CVE-2023-1281 https://www.cve.org/CVERecord?id=CVE-2023-1281 Référence CVE CVE-2023-1652 https://www.cve.org/CVERecord?id=CVE-2023-1652 Référence CVE CVE-2023-1829 https://www.cve.org/CVERecord?id=CVE-2023-1829 Référence CVE CVE-2023-1859 https://www.cve.org/CVERecord?id=CVE-2023-1859 Référence CVE CVE-2023-1872 https://www.cve.org/CVERecord?id=CVE-2023-1872 Référence CVE CVE-2023-23455 https://www.cve.org/CVERecord?id=CVE-2023-23455 Référence CVE CVE-2023-26545 https://www.cve.org/CVERecord?id=CVE-2023-26545 Gestion détaillée du document le 12 mai 2023 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-2023-AVI-0359Multiples 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 une exécution de code arbitraire, un déni de service et une élévation de privilèges.

Official advisory
CERT-FR · French · CERTFR-2023-AVI-0345Multiples 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 une élévation de privilèges, une exécution de code arbitraire à distance et une atteinte à la confidentialité des données.

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
5.7 ≤ 5.17
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 12 Apr 2023 · Last source change 13 Feb 2025, 16:39 UTC · CWE-416 · Use After Free

CVE recordCVE.org · 5.1
CVSS sourceCNA
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-2023-24074
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-2023-1872 · cve.blacktree.nl