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Full vulnerability report · 2024
CVE-2023-52633High confidence

um: time-travel: fix time corruption

Linux · Linux

5.0MediumCVSS 3.1
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

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-azure-fdeAffected, 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 11 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-2023-57257

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 actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: um: time-travel: fix time corruption In 'basic' time-travel mode (without =inf-cpu or =ext), we still get timer interrupts. These can happen at arbitrary points in time, i.e. while in timer_read(), which pushes time forward just a little bit. Then, if we happen to get the interrupt after calculating the new time to push to, but before actually finishing that, the interrupt will set the time to a value that's incompatible with the forward, and we'll crash because time goes backwards when we do the forwarding. Fix this by reading the time_travel_time, calculating the adjustment, and doing the adjustment all with interrupts disabled.

What

In the Linux kernel, the following vulnerability has been resolved: um: time-travel: fix time corruption In 'basic' time-travel mode (without =inf-cpu or =ext), we still get timer interrupts. These can happen at arbitrary points in time, i.e. while in timer_read(), which pushes time forward just a little bit. Then, if we happen to get the interrupt after calculating the new time to push to, but before actually finishing that, the interrupt will set the time to a value that's incompatible with the forward, and we'll crash because time goes backwards when we do the forwarding. Fix this by reading the time_travel_time, calculating the adjustment, and doing the adjustment all with interrupts disabled.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

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

What

In the Linux kernel, the following vulnerability has been resolved: um: time-travel: fix time corruption In 'basic' time-travel mode (without =inf-cpu or =ext), we still get timer interrupts. These can happen at arbitrary points in time, i.e. while in timer_read(), which pushes time forward just a little bit. Then, if we happen to get the interrupt after calculating the new time to push to, but before actually finishing that, the interrupt will set the time to a value that's incompatible with the forward, and we'll crash because time goes backwards when we do the forwarding. Fix this by reading the time_travel_time, calculating the adjustment, and doing the adjustment all with interrupts disabled.

Why

A bounds error lets data be written beyond the intended memory region, potentially corrupting control data.

How

An attacker operating through local access may attempt exploitation with low 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.
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 → Out-of-bounds Write → disrupt the affected service
Attack surface
Local
Privileges required
Low: a basic authenticated account is required
User interaction
Required interaction required
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-787

CWE-787: Out-of-bounds Write. The product writes 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:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/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.UIRequiredUser interaction: Another user must perform an action for exploitation to succeed.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.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.
Denial of serviceCWE-787
A

Official authority intelligence

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

BSI · German · WID-SEC-2024-0749Linux Kernel: Mehrere Schwachstellen

Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service oder einen nicht näher spezifizierten Angriff durchzuführen.

Official advisory ↗
Cyber Security Agency of Singapore · English · CSA-SB-20240403Security Bulletin 03 Apr 2024

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 03 Apr 2024, published on 3 April 2024. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0456Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2023-52615 Référence CVE CVE-2023-52616 https://www.cve.org/CVERecord?id=CVE-2023-52616 Référence CVE CVE-2023-52617 https://www.cve.org/CVERecord?id=CVE-2023-52617 Référence CVE CVE-2023-52618 https://www.cve.org/CVERecord?id=CVE-2023-52618 Référence CVE CVE-2023-52619 https://www.cve.org/CVERecord?id=CVE-2023-52619 Référence CVE CVE-2023-52622 https://www.cve.org/CVERecord?id=CVE-2023-52622 Référence CVE CVE-2023-52623 https://www.cve.org/CVERecord?id=CVE-2023-52623 Référence CVE CVE-2023-52627 https://www.cve.org/CVERecord?id=CVE-2023-52627 Référence CVE CVE-2023-52631 https://www.cve.org/CVERecord?id=CVE-2023-52631 Référence CVE CVE-2023-52633 https://www.cve.org/CVERecord?id=CVE-2023-52633 Référence CVE CVE-2023-52635 https://www.cve.org/CVERecord?id=CVE-2023-52635 Référence CVE CVE-2023-52637 https://www.cve.org/CVERecord?id=CVE-2023-52637 Référence CVE CVE-2023-52638 https://www.cve.org/CVERecord?id=CVE-2023-52638 Référence CVE CVE-2023-52642 https://www.cve.org/CVERecord?id=CVE-2023-52642 Référence CVE CVE-2023-52643 https://www.cve.org/CVERecord?id=CVE-2023-52643 Référence CVE CVE-2024-1151 https://www.cve.org/CVERecord?id=CVE-2024-1151 Référence CVE CVE-2024-2201 https://www.cve.org/CVERecord?id=CVE-2024-2201 Référence CVE CVE-2024-23849 https://www.cve.org/CVERecord?id=CVE-

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0439Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2023-52615 Référence CVE CVE-2023-52616 https://www.cve.org/CVERecord?id=CVE-2023-52616 Référence CVE CVE-2023-52617 https://www.cve.org/CVERecord?id=CVE-2023-52617 Référence CVE CVE-2023-52618 https://www.cve.org/CVERecord?id=CVE-2023-52618 Référence CVE CVE-2023-52619 https://www.cve.org/CVERecord?id=CVE-2023-52619 Référence CVE CVE-2023-52622 https://www.cve.org/CVERecord?id=CVE-2023-52622 Référence CVE CVE-2023-52623 https://www.cve.org/CVERecord?id=CVE-2023-52623 Référence CVE CVE-2023-52627 https://www.cve.org/CVERecord?id=CVE-2023-52627 Référence CVE CVE-2023-52631 https://www.cve.org/CVERecord?id=CVE-2023-52631 Référence CVE CVE-2023-52633 https://www.cve.org/CVERecord?id=CVE-2023-52633 Référence CVE CVE-2023-52635 https://www.cve.org/CVERecord?id=CVE-2023-52635 Référence CVE CVE-2023-52637 https://www.cve.org/CVERecord?id=CVE-2023-52637 Référence CVE CVE-2023-52638 https://www.cve.org/CVERecord?id=CVE-2023-52638 Référence CVE CVE-2023-52642 https://www.cve.org/CVERecord?id=CVE-2023-52642 Référence CVE CVE-2023-52643 https://www.cve.org/CVERecord?id=CVE-2023-52643 Référence CVE CVE-2024-1151 https://www.cve.org/CVERecord?id=CVE-2024-1151 Référence CVE CVE-2024-2201 https://www.cve.org/CVERecord?id=CVE-2024-2201 Référence CVE CVE-2024-23849 https://www.cve.org/CVERecord?id=CVE-

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0422Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2023-52615 Référence CVE CVE-2023-52616 https://www.cve.org/CVERecord?id=CVE-2023-52616 Référence CVE CVE-2023-52617 https://www.cve.org/CVERecord?id=CVE-2023-52617 Référence CVE CVE-2023-52618 https://www.cve.org/CVERecord?id=CVE-2023-52618 Référence CVE CVE-2023-52619 https://www.cve.org/CVERecord?id=CVE-2023-52619 Référence CVE CVE-2023-52622 https://www.cve.org/CVERecord?id=CVE-2023-52622 Référence CVE CVE-2023-52623 https://www.cve.org/CVERecord?id=CVE-2023-52623 Référence CVE CVE-2023-52627 https://www.cve.org/CVERecord?id=CVE-2023-52627 Référence CVE CVE-2023-52631 https://www.cve.org/CVERecord?id=CVE-2023-52631 Référence CVE CVE-2023-52633 https://www.cve.org/CVERecord?id=CVE-2023-52633 Référence CVE CVE-2023-52635 https://www.cve.org/CVERecord?id=CVE-2023-52635 Référence CVE CVE-2023-52637 https://www.cve.org/CVERecord?id=CVE-2023-52637 Référence CVE CVE-2023-52638 https://www.cve.org/CVERecord?id=CVE-2023-52638 Référence CVE CVE-2023-52642 https://www.cve.org/CVERecord?id=CVE-2023-52642 Référence CVE CVE-2023-52643 https://www.cve.org/CVERecord?id=CVE-2023-52643 Référence CVE CVE-2024-1151 https://www.cve.org/CVERecord?id=CVE-2024-1151 Référence CVE CVE-2024-2201 https://www.cve.org/CVERecord?id=CVE-2024-2201 Référence CVE CVE-2024-23849 https://www.cve.org/CVERecord?id=CVE-

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0383Multiples vulnérabilités dans le noyau Linux d'Ubuntu

d?id=CVE-2023-52618 Référence CVE CVE-2023-52619 https://www.cve.org/CVERecord?id=CVE-2023-52619 Référence CVE CVE-2023-52621 https://www.cve.org/CVERecord?id=CVE-2023-52621 Référence CVE CVE-2023-52622 https://www.cve.org/CVERecord?id=CVE-2023-52622 Référence CVE CVE-2023-52623 https://www.cve.org/CVERecord?id=CVE-2023-52623 Référence CVE CVE-2023-52626 https://www.cve.org/CVERecord?id=CVE-2023-52626 Référence CVE CVE-2023-52627 https://www.cve.org/CVERecord?id=CVE-2023-52627 Référence CVE CVE-2023-52631 https://www.cve.org/CVERecord?id=CVE-2023-52631 Référence CVE CVE-2023-52632 https://www.cve.org/CVERecord?id=CVE-2023-52632 Référence CVE CVE-2023-52633 https://www.cve.org/CVERecord?id=CVE-2023-52633 Référence CVE CVE-2023-52635 https://www.cve.org/CVERecord?id=CVE-2023-52635 Référence CVE CVE-2023-52637 https://www.cve.org/CVERecord?id=CVE-2023-52637 Référence CVE CVE-2023-52638 https://www.cve.org/CVERecord?id=CVE-2023-52638 Référence CVE CVE-2023-52642 https://www.cve.org/CVERecord?id=CVE-2023-52642 Référence CVE CVE-2023-52643 https://www.cve.org/CVERecord?id=CVE-2023-52643 Référence CVE CVE-2023-6356 https://www.cve.org/CVERecord?id=CVE-2023-6356 Référence CVE CVE-2023-6535 https://www.cve.org/CVERecord?id=CVE-2023-6535 Référence CVE CVE-2023-6536 https://www.cve.org/CVERecord?id=CVE-2

Official advisory ↗
CERT-FR · French · CERTFR-2024-AVI-0334Multiples vulnérabilités dans le noyau Linux de Debian

d?id=CVE-2023-52618 Référence CVE CVE-2023-52619 https://www.cve.org/CVERecord?id=CVE-2023-52619 Référence CVE CVE-2023-52620 https://www.cve.org/CVERecord?id=CVE-2023-52620 Référence CVE CVE-2023-52621 https://www.cve.org/CVERecord?id=CVE-2023-52621 Référence CVE CVE-2023-52622 https://www.cve.org/CVERecord?id=CVE-2023-52622 Référence CVE CVE-2023-52623 https://www.cve.org/CVERecord?id=CVE-2023-52623 Référence CVE CVE-2023-52630 https://www.cve.org/CVERecord?id=CVE-2023-52630 Référence CVE CVE-2023-52631 https://www.cve.org/CVERecord?id=CVE-2023-52631 Référence CVE CVE-2023-52632 https://www.cve.org/CVERecord?id=CVE-2023-52632 Référence CVE CVE-2023-52633 https://www.cve.org/CVERecord?id=CVE-2023-52633 Référence CVE CVE-2023-52635 https://www.cve.org/CVERecord?id=CVE-2023-52635 Référence CVE CVE-2023-52637 https://www.cve.org/CVERecord?id=CVE-2023-52637 Référence CVE CVE-2023-52638 https://www.cve.org/CVERecord?id=CVE-2023-52638 Référence CVE CVE-2023-52639 https://www.cve.org/CVERecord?id=CVE-2023-52639 Référence CVE CVE-2023-52640 https://www.cve.org/CVERecord?id=CVE-2023-52640 Référence CVE CVE-2023-52641 https://www.cve.org/CVERecord?id=CVE-2023-52641 Référence CVE CVE-2023-6270 https://www.cve.org/CVERecord?id=CVE-2023-6270 Référence CVE CVE-2023-7042 https://www.cve.org/CVERecord?id=CVE

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2023-028446Linux の Linux Kernel における境界外書き込みに関する脆弱性

Linux の Linux Kernel には、境界外書き込みに関する脆弱性が存在します。

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
Linux: 065038706f77a56754e8f0c2556dab7e22dfe577 < 0c7478a2da3f5fe106b4658338873d50c86ac7ab, 065038706f77a56754e8f0c2556dab7e22dfe577 < 4f7dad73df4cdb2b7042103d3922745d040ad025, 065038706f77a56754e8f0c2556dab7e22dfe577 < de3e9d8e8d1ae0a4d301109d1ec140796901306c, 065038706f77a56754e8f0c2556dab7e22dfe577 < b427f55e9d4185f6f17cc1e3296eb8d0c4425283, 065038706f77a56754e8f0c2556dab7e22dfe577 < abe4eaa8618bb36c2b33e9cdde0499296a23448c, 5.3
Fixed
Linux: < 5.3, 5.15.149 ≤ 5.15.*, 6.1.77 ≤ 6.1.*, 6.6.16 ≤ 6.6.*, 6.7.4 ≤ 6.7.*, 6.8 ≤ *
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 2 Apr 2024 · Last source change 11 May 2026, 19:30 UTC · CWE-787 · Out-of-bounds Write

CVE recordCVE.org · 5.2
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-2023-57257
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
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 ↗

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-2023-52633 · cve.blacktree.nl