Crash due to a null pointer dereference in the dn_nsp_send function
n/a · kernel
6.5MediumCVSS 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 release
Source package
Vendor state
Fixed version
Evidence
Ubuntu 24.04 LTSnoble · standard archive
linux-raspi-realtime
Affected, no fix publishedCanonical OVAL identifies this running kernel flavour as affected and does not publish a fixed package version in this definition.
Structured product status and remediation from the issuing vendor. Product-state explanations are always visible; large lists can be searched or downloaded.
1 current
SSA-794697 · CSAF 2.0 · revision 9 · interimSiemens ProductCERTSSA-794697: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 TM MFP before 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
A null pointer dereference flaw was found in the Linux kernel's DECnet networking protocol. This issue could allow a remote user to crash the system.
Remediation
Update to V1.1 or later version
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-2023-44006
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 null pointer dereference flaw was found in the Linux kernel's DECnet networking protocol. This issue could allow a remote user to crash the system.
What
A null pointer dereference flaw was found in the Linux kernel's DECnet networking protocol. This issue could allow a remote user to crash the system.
Why
The product dereferences a pointer that it expects to be valid but is NULL.
How
An attacker operating through a network path may attempt exploitation with low privileges. If successful, the issue may disrupt the affected service.
What
A null pointer dereference flaw was found in the Linux kernel's DECnet networking protocol. This issue could allow a remote user to crash the system.
Why
The product dereferences a pointer that it expects to be valid but is NULL.
How
An attacker operating through a network path 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.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
a network path → NULL Pointer Dereference → disrupt the affected service
Attack surface
Network
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-476: NULL Pointer Dereference. The product dereferences a pointer that it expects to be valid but is NULL.
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: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.
AVNetworkAttack vector: The vulnerable component can be reached over a network.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
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.
NetworkDenial of serviceCWE-476Public exploit reference
A
Official authority intelligence
Only matched European and national findings are included. Language selectors and unavailable sources are omitted.
ENISA EUVD · EUVD-2023-44006Official EUVD mapping
0 linked advisory records.
Official EUVD recordBSI · German · WID-SEC-W-2023-1564Linux Kernel: Schwachstelle ermöglicht Denial of Service
Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um einen Denial of Service Angriff durchzuführen.
Official advisoryCERT-FR · French · CERTFR-2023-AVI-0895Multiples vulnérabilités dans le noyau Linux de Ubuntu
Official advisoryCERT-FR · French · CERTFR-2023-AVI-0817Multiples 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
à distance, un contournement de la politique de sécurité et une atteinte
à la confidentialité des données.
Official advisoryCERT-FR · French · CERTFR-2023-AVI-0813Multiples vulnérabilités dans le noyau Linux d'Ubuntu
Official advisoryCERT-FR · French · CERTFR-2023-AVI-0601Multiples vulnérabilités dans le noyau Linux de Debian
De multiples vulnérabilités ont été découvertes dans le noyau Linux de
Debian. Certaines d'entre elles permettent à un attaquant de provoquer
une élévation de privilèges, une atteinte à la confidentialité des
données.
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
6.5-rc1
Action
Update to V1.1 or later version
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04
Evidence and provenance
Published 30 Jun 2023 · Last source change 5 Mar 2025, 18:55 UTC · CWE-476 · NULL Pointer Dereference
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
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.
CVE-2023-3338: Crash due to a null pointer dereference in the dn_nsp_send function | BlackTree