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Full vulnerability report · 2025
CVE-2022-50428High confidence

ext4: fix off-by-one errors in fast-commit block filling

Linux · Linux

5.5MediumCVSS 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.

9 package states
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-6.11Affected, 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
Ubuntu 24.04 LTSnoble · standard archivelinux-gcp-6.11Affected, 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
Ubuntu 24.04 LTSnoble · standard archivelinux-hwe-6.11Affected, 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
Ubuntu 24.04 LTSnoble · standard archivelinux-intelAffected, 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
Ubuntu 24.04 LTSnoble · standard archivelinux-lowlatency-hwe-6.11Affected, 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
Ubuntu 24.04 LTSnoble · standard archivelinux-oem-6.11Affected, 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
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
Ubuntu 24.04 LTSnoble · standard archivelinux-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
Ubuntu 24.04 LTSnoble · standard archivelinux-riscvAffected, 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-2025-32857

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: ext4: fix off-by-one errors in fast-commit block filling Due to several different off-by-one errors, or perhaps due to a late change in design that wasn't fully reflected in the code that was actually merged, there are several very strange constraints on how fast-commit blocks are filled with tlv entries: - tlvs must start at least 10 bytes before the end of the block, even though the minimum tlv length is 8. Otherwise, the replay code will ignore them. (BUG: ext4_fc_reserve_space() could violate this requirement if called with a len of blocksize - 9 or blocksize - 8. Fortunately, this doesn't seem to happen currently.) - tlvs must end at least 1 byte before the end of the block. Otherwise the replay code will consider them to be invalid. This quirk contributed to a bug (fixed by an earlier commit) where uninitialized memory was being leaked to disk in the last byte of blocks. Also, strangely these constraints don't apply to the replay code in e2fsprogs, which will accept any tlvs in the blocks (with no bounds checks at all, but that is a separate issue...). Given that this all seems to be a bug, let's fix it by just filling blocks with tlv entries in the natural way. Note that old kernels will be unable to replay fast-commit journals created by kernels that have this commit.

What

In the Linux kernel, the following vulnerability has been resolved: ext4: fix off-by-one errors in fast-commit block filling Due to several different off-by-one errors, or perhaps due to a late change in design that wasn't fully reflected in the code that was actually merged, there are several very strange constraints on how fast-commit blocks are filled with tlv entries: - tlvs must start at least 10 bytes before the end of the block, even though the minimum tlv length is 8. Otherwise, the replay code will ignore them. (BUG: ext4_fc_reserve_space() could violate this requirement if called with a len of blocksize - 9 or blocksize - 8. Fortunately, this doesn't seem to happen currently.) - tlvs must end at least 1 byte before the end of the block. Otherwise the replay code will consider them to be invalid. This quirk contributed to a bug (fixed by an earlier commit) where uninitialized memory was being leaked to disk in the last byte of blocks. Also, strangely these constraints don't apply to the replay code in e2fsprogs, which will accept any tlvs in the blocks (with no bounds checks at all, but that is a separate issue...). Given that this all seems to be a bug, let's fix it by just filling blocks with tlv entries in the natural way. Note that old kernels will be unable to replay fast-commit journals created by kernels that have this commit.

Why

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

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

In the Linux kernel, the following vulnerability has been resolved: ext4: fix off-by-one errors in fast-commit block filling Due to several different off-by-one errors, or perhaps due to a late change in design that wasn't fully reflected in the code that was actually merged, there are several very strange constraints on how fast-commit blocks are filled with tlv entries: - tlvs must start at least 10 bytes before the end of the block, even though the minimum tlv length is 8. Otherwise, the replay code will ignore them. (BUG: ext4_fc_reserve_space() could violate this requirement if called with a len of blocksize - 9 or blocksize - 8. Fortunately, this doesn't seem to happen currently.) - tlvs must end at least 1 byte before the end of the block. Otherwise the replay code will consider them to be invalid. This quirk contributed to a bug (fixed by an earlier commit) where uninitialized memory was being leaked to disk in the last byte of blocks. Also, strangely these constraints don't apply to the replay code in e2fsprogs, which will accept any tlvs in the blocks (with no bounds checks at all, but that is a separate issue...). Given that this all seems to be a bug, let's fix it by just filling blocks with tlv entries in the natural way. Note that old kernels will be unable to replay fast-commit journals created by kernels that have this commit.

Why

A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

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 → Off-by-one Error → 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-193

CWE-193: Off-by-one Error. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value.

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: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.UINoneUser interaction: No action by another user is required.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.
CWE-193
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2025-2187Linux Kernel: Mehrere Schwachstellen ermöglichen Denial of Service

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen und um nicht nähere beschriebene Effekte zu verursachen.

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0921Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2022-50410 Référence CVE CVE-2022-50411 https://www.cve.org/CVERecord?id=CVE-2022-50411 Référence CVE CVE-2022-50414 https://www.cve.org/CVERecord?id=CVE-2022-50414 Référence CVE CVE-2022-50417 https://www.cve.org/CVERecord?id=CVE-2022-50417 Référence CVE CVE-2022-50419 https://www.cve.org/CVERecord?id=CVE-2022-50419 Référence CVE CVE-2022-50422 https://www.cve.org/CVERecord?id=CVE-2022-50422 Référence CVE CVE-2022-50423 https://www.cve.org/CVERecord?id=CVE-2022-50423 Référence CVE CVE-2022-50425 https://www.cve.org/CVERecord?id=CVE-2022-50425 Référence CVE CVE-2022-50427 https://www.cve.org/CVERecord?id=CVE-2022-50427 Référence CVE CVE-2022-50428 https://www.cve.org/CVERecord?id=CVE-2022-50428 Référence CVE CVE-2022-50429 https://www.cve.org/CVERecord?id=CVE-2022-50429 Référence CVE CVE-2022-50430 https://www.cve.org/CVERecord?id=CVE-2022-50430 Référence CVE CVE-2022-50431 https://www.cve.org/CVERecord?id=CVE-2022-50431 Référence CVE CVE-2022-50432 https://www.cve.org/CVERecord?id=CVE-2022-50432 Référence CVE CVE-2022-50434 https://www.cve.org/CVERecord?id=CVE-2022-50434 Référence CVE CVE-2022-50435 https://www.cve.org/CVERecord?id=CVE-2022-50435 Référence CVE CVE-2022-50436 https://www.cve.org/CVERecord?id=CVE-2022-50436 Référence CVE CVE-2022-50437 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0895Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2022-50412 Référence CVE CVE-2022-50414 https://www.cve.org/CVERecord?id=CVE-2022-50414 Référence CVE CVE-2022-50417 https://www.cve.org/CVERecord?id=CVE-2022-50417 Référence CVE CVE-2022-50418 https://www.cve.org/CVERecord?id=CVE-2022-50418 Référence CVE CVE-2022-50419 https://www.cve.org/CVERecord?id=CVE-2022-50419 Référence CVE CVE-2022-50422 https://www.cve.org/CVERecord?id=CVE-2022-50422 Référence CVE CVE-2022-50423 https://www.cve.org/CVERecord?id=CVE-2022-50423 Référence CVE CVE-2022-50425 https://www.cve.org/CVERecord?id=CVE-2022-50425 Référence CVE CVE-2022-50427 https://www.cve.org/CVERecord?id=CVE-2022-50427 Référence CVE CVE-2022-50428 https://www.cve.org/CVERecord?id=CVE-2022-50428 Référence CVE CVE-2022-50429 https://www.cve.org/CVERecord?id=CVE-2022-50429 Référence CVE CVE-2022-50430 https://www.cve.org/CVERecord?id=CVE-2022-50430 Référence CVE CVE-2022-50431 https://www.cve.org/CVERecord?id=CVE-2022-50431 Référence CVE CVE-2022-50432 https://www.cve.org/CVERecord?id=CVE-2022-50432 Référence CVE CVE-2022-50433 https://www.cve.org/CVERecord?id=CVE-2022-50433 Référence CVE CVE-2022-50434 https://www.cve.org/CVERecord?id=CVE-2022-50434 Référence CVE CVE-2022-50435 https://www.cve.org/CVERecord?id=CVE-2022-50435 Référence CVE CVE-2022-50436 https://www.cve.org/CVERecord?id=

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
aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 18f28f13301d1afb8cea9c4ddcecdbff14488ec6; aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 5ca65dffdead16572ca046c43fb576b227f7f635; aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 5439ad45c0d0c8db41eb6f4dce6f778f15a5ee16; aa75f4d3daaeb1389b9cce9d6b84401eaf228d4e < 48a6a66db82b8043d298a630f22c62d43550cae5; 5.10
Fixed
< 5.10; 5.15.87 ≤ 5.15.*; 6.0.18 ≤ 6.0.*; 6.1.4 ≤ 6.1.*; 6.2 ≤ *
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 1 Oct 2025 · Last source change 11 May 2026, 19:19 UTC · CWE-193 · Off-by-one Error

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-2025-32857
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-2022-50428 · cve.blacktree.nl