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Full vulnerability report · 2024
CVE-2022-48828High confidence

NFSD: Fix ia_size underflow

Linux · Linux

9.1CriticalCVSS 3.1
Recommended action
Within 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

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 4 Sept 2026
Direct vendor intelligence

Authoritative vendor CSAF and VEX advisories

Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.

2 current
SSA-265688 · CSAF 2.0 · revision 13 · interimSiemens ProductCERTSSA-265688: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP V1.1
1 known affected

The vendor explicitly identifies these products as affected by this CVE.

  • SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
Summary
NFSD: Vulnerability caused by an underflow in ia_size due to a mismatch between signed and unsigned 64-bit file size values, which can cause issues when handling large file sizes from NFS clients.
Remediation
Limit access to the interactive shell of the additional GNU/Linux subssytem to trusted personnel only.
SSA-355557 · CSAF 2.0 · revision 3 · interimSiemens ProductCERTSSA-355557: Multiple Vulnerabilities in Third-Party Components in SINEC OS before V3.2
3 known not affected

The vendor explicitly states that these products are not affected by this CVE.

  • RUGGEDCOM RST2428P (6GK6242-6PA00)
  • SCALANCE XC-300/XR-300/XC-400/XR-500WG/XR-500 family
  • SCALANCE XCM-/XRM-/XCH-/XRH-300 family
Summary
NFSD: Vulnerability caused by an underflow in ia_size due to a mismatch between signed and unsigned 64-bit file size values, which can cause issues when handling large file sizes from NFS clients.
Remediation
No remediation text is recorded.
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-2022-53707

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 72 hours

Critical technical impact with a remotely reachable, unauthenticated path; no CISA KEV confirmation is currently recorded.

Patch available
01

What, why and how

In the Linux kernel, the following vulnerability has been resolved: NFSD: Fix ia_size underflow iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and NFSv4 both define file size as an unsigned 64-bit type. Thus there is a range of valid file size values an NFS client can send that is already larger than Linux can handle. Currently decode_fattr4() dumps a full u64 value into ia_size. If that value happens to be larger than S64_MAX, then ia_size underflows. I'm about to fix up the NFSv3 behavior as well, so let's catch the underflow in the common code path: nfsd_setattr().

What

In the Linux kernel, the following vulnerability has been resolved: NFSD: Fix ia_size underflow iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and NFSv4 both define file size as an unsigned 64-bit type. Thus there is a range of valid file size values an NFS client can send that is already larger than Linux can handle. Currently decode_fattr4() dumps a full u64 value into ia_size. If that value happens to be larger than S64_MAX, then ia_size underflows. I'm about to fix up the NFSv3 behavior as well, so let's catch the underflow in the common code path: nfsd_setattr().

Why

The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. 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: NFSD: Fix ia_size underflow iattr::ia_size is a loff_t, which is a signed 64-bit type. NFSv3 and NFSv4 both define file size as an unsigned 64-bit type. Thus there is a range of valid file size values an NFS client can send that is already larger than Linux can handle. Currently decode_fattr4() dumps a full u64 value into ia_size. If that value happens to be larger than S64_MAX, then ia_size underflows. I'm about to fix up the NFSv3 behavior as well, so let's catch the underflow in the common code path: nfsd_setattr().

Why

The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. 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
a network path → Integer Underflow (Wrap or Wraparound) → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
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-191

CWE-191: Integer Underflow (Wrap or Wraparound). The product subtracts one value from another, such that the result is less than the minimum allowable integer value, which produces a value that is not equal to the correct result.

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

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

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing 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.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
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.
NetworkUnauthenticatedCWE-191
A

Official authority intelligence

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

BSI · German · WID-SEC-W-2024-1625Linux Kernel: Mehrere Schwachstellen ermöglichen nicht spezifizierten Angriff

Ein Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen nicht näher spezifizierten Angriff durchzuführen.

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0677Multiples vulnérabilités dans les produits Siemens

3808 du 12 août 2025 https://cert-portal.siemens.com/productcert/html/ssa-693808.html Bulletin de sécurité Siemens SSA-707630 du 12 août 2025 https://cert-portal.siemens.com/productcert/html/ssa-707630.html Bulletin de sécurité Siemens SSA-894058 du 12 août 2025 https://cert-portal.siemens.com/productcert/html/ssa-894058.html Référence CVE CVE-2021-44879 https://www.cve.org/CVERecord?id=CVE-2021-44879 Référence CVE CVE-2021-47316 https://www.cve.org/CVERecord?id=CVE-2021-47316 Référence CVE CVE-2022-48666 https://www.cve.org/CVERecord?id=CVE-2022-48666 Référence CVE CVE-2022-48827 https://www.cve.org/CVERecord?id=CVE-2022-48827 Référence CVE CVE-2022-48828 https://www.cve.org/CVERecord?id=CVE-2022-48828 Référence CVE CVE-2022-48829 https://www.cve.org/CVERecord?id=CVE-2022-48829 Référence CVE CVE-2022-48935 https://www.cve.org/CVERecord?id=CVE-2022-48935 Référence CVE CVE-2022-49034 https://www.cve.org/CVERecord?id=CVE-2022-49034 Référence CVE CVE-2023-3567 https://www.cve.org/CVERecord?id=CVE-2023-3567 Référence CVE CVE-2023-35827 https://www.cve.org/CVERecord?id=CVE-2023-35827 Référence CVE CVE-2023-39198 https://www.cve.org/CVERecord?id=CVE-2023-39198 Référence CVE CVE-2023-45863 https://www.cve.org/CVERecord?id=CVE-2023-45863 Référence CVE CVE-2023-46343 https://www.cve.org/CVERecord?id=CV

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0717Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2022-48818 Référence CVE CVE-2022-48820 https://www.cve.org/CVERecord?id=CVE-2022-48820 Référence CVE CVE-2022-48821 https://www.cve.org/CVERecord?id=CVE-2022-48821 Référence CVE CVE-2022-48822 https://www.cve.org/CVERecord?id=CVE-2022-48822 Référence CVE CVE-2022-48823 https://www.cve.org/CVERecord?id=CVE-2022-48823 Référence CVE CVE-2022-48824 https://www.cve.org/CVERecord?id=CVE-2022-48824 Référence CVE CVE-2022-48825 https://www.cve.org/CVERecord?id=CVE-2022-48825 Référence CVE CVE-2022-48826 https://www.cve.org/CVERecord?id=CVE-2022-48826 Référence CVE CVE-2022-48827 https://www.cve.org/CVERecord?id=CVE-2022-48827 Référence CVE CVE-2022-48828 https://www.cve.org/CVERecord?id=CVE-2022-48828 Référence CVE CVE-2022-48829 https://www.cve.org/CVERecord?id=CVE-2022-48829 Référence CVE CVE-2022-48830 https://www.cve.org/CVERecord?id=CVE-2022-48830 Référence CVE CVE-2022-48831 https://www.cve.org/CVERecord?id=CVE-2022-48831 Référence CVE CVE-2022-48834 https://www.cve.org/CVERecord?id=CVE-2022-48834 Référence CVE CVE-2022-48835 https://www.cve.org/CVERecord?id=CVE-2022-48835 Référence CVE CVE-2022-48836 https://www.cve.org/CVERecord?id=CVE-2022-48836 Référence CVE CVE-2022-48837 https://www.cve.org/CVERecord?id=CVE-2022-48837 Référence CVE CVE-2022-48838 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0695Multiples vulnérabilités dans le noyau Linux de Red Hat

ord?id=CVE-2021-47383 Référence CVE CVE-2021-47385 https://www.cve.org/CVERecord?id=CVE-2021-47385 Référence CVE CVE-2021-47566 https://www.cve.org/CVERecord?id=CVE-2021-47566 Référence CVE CVE-2021-47606 https://www.cve.org/CVERecord?id=CVE-2021-47606 Référence CVE CVE-2021-47624 https://www.cve.org/CVERecord?id=CVE-2021-47624 Référence CVE CVE-2022-1011 https://www.cve.org/CVERecord?id=CVE-2022-1011 Référence CVE CVE-2022-48627 https://www.cve.org/CVERecord?id=CVE-2022-48627 Référence CVE CVE-2022-48637 https://www.cve.org/CVERecord?id=CVE-2022-48637 Référence CVE CVE-2022-48827 https://www.cve.org/CVERecord?id=CVE-2022-48827 Référence CVE CVE-2022-48828 https://www.cve.org/CVERecord?id=CVE-2022-48828 Référence CVE CVE-2022-48829 https://www.cve.org/CVERecord?id=CVE-2022-48829 Référence CVE CVE-2023-20569 https://www.cve.org/CVERecord?id=CVE-2023-20569 Référence CVE CVE-2023-4622 https://www.cve.org/CVERecord?id=CVE-2023-4622 Référence CVE CVE-2023-52439 https://www.cve.org/CVERecord?id=CVE-2023-52439 Référence CVE CVE-2023-52448 https://www.cve.org/CVERecord?id=CVE-2023-52448 Référence CVE CVE-2023-52610 https://www.cve.org/CVERecord?id=CVE-2023-52610 Référence CVE CVE-2023-52639 https://www.cve.org/CVERecord?id=CVE-2023-52639 Référence CVE CVE-2023-52651 https://www.cve.org/CVERecord?id=CV

Official advisory
CERT-FR · French · CERTFR-2024-AVI-0693Multiples vulnérabilités dans le noyau Linux de SUSE

d?id=CVE-2022-48818 Référence CVE CVE-2022-48820 https://www.cve.org/CVERecord?id=CVE-2022-48820 Référence CVE CVE-2022-48821 https://www.cve.org/CVERecord?id=CVE-2022-48821 Référence CVE CVE-2022-48822 https://www.cve.org/CVERecord?id=CVE-2022-48822 Référence CVE CVE-2022-48823 https://www.cve.org/CVERecord?id=CVE-2022-48823 Référence CVE CVE-2022-48824 https://www.cve.org/CVERecord?id=CVE-2022-48824 Référence CVE CVE-2022-48825 https://www.cve.org/CVERecord?id=CVE-2022-48825 Référence CVE CVE-2022-48826 https://www.cve.org/CVERecord?id=CVE-2022-48826 Référence CVE CVE-2022-48827 https://www.cve.org/CVERecord?id=CVE-2022-48827 Référence CVE CVE-2022-48828 https://www.cve.org/CVERecord?id=CVE-2022-48828 Référence CVE CVE-2022-48829 https://www.cve.org/CVERecord?id=CVE-2022-48829 Référence CVE CVE-2022-48830 https://www.cve.org/CVERecord?id=CVE-2022-48830 Référence CVE CVE-2022-48831 https://www.cve.org/CVERecord?id=CVE-2022-48831 Référence CVE CVE-2022-48834 https://www.cve.org/CVERecord?id=CVE-2022-48834 Référence CVE CVE-2022-48835 https://www.cve.org/CVERecord?id=CVE-2022-48835 Référence CVE CVE-2022-48836 https://www.cve.org/CVERecord?id=CVE-2022-48836 Référence CVE CVE-2022-48837 https://www.cve.org/CVERecord?id=CVE-2022-48837 Référence CVE CVE-2022-48838 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
SIMATIC S7-1500 TM MFP - GNU/Linux subsystem
Fixed
< 2.6.12; 5.4.295 ≤ 5.4.*; 5.10.220 ≤ 5.10.*; 5.15.24 ≤ 5.15.*; 5.16.10 ≤ 5.16.*; 5.17 ≤ *
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
Limit access to the interactive shell of the additional GNU/Linux subssytem to trusted personnel only.
04

Evidence and provenance

Published 16 Jul 2024 · Last source change 5 Aug 2026, 08:52 UTC · CWE-191 · Integer Underflow (Wrap or Wraparound)

CVE recordCVE.org · 5.2
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-2022-53707
Product sourceVendor CSAF · Siemens ProductCERT
Remediation sourceVendor CSAF · Siemens ProductCERT
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-2022-48828 · cve.blacktree.nl