HighCVE-2026-46243

Linux Kernel: security vulnerability (CVE-2026-46243)

Published 01.06.2026Last modified 15.10.2026Sources: SUSE, Ubuntu, Red Hat, Siemens ProductCERT, BSI, CVE.org, Msrc Update Guide

Public exploit

What is affected, what to do

In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.spnego descriptions cifs.spnego key descriptions contain authority-bearing fields such as pid, uid, creduid, and upcall_target that cifs.upcall treats as kernel-originating inputs. However, userspace can also create keys of this type through request_key(2) or add_key(2), allowing those fields to be supplied without CIFS origin.

An exploit is publicly available. Update Linux Kernel to version 5.10.258, Linux Kernel to version 5.15.209, Linux Kernel to version 6.1.175.

Affected: Linux Kernel lt 2.6.24..5.10.258
Linux Kernel lt 5.11..5.15.209
Linux Kernel lt 5.16..6.1.175
Linux Kernel lt 6.2..6.6.142
Linux Kernel lt 6.7..6.12.92
Linux Kernel lt 6.13..6.18.34
Linux Kernel lt 6.19..7.0.11
Fixed in: Linux Kernel 5.10.258
Linux Kernel 5.15.209
Linux Kernel 6.1.175
Linux Kernel 6.6.142
Linux Kernel 6.12.92
Linux Kernel 6.18.34
Linux Kernel 7.0.11
Linux Kernel 7.1

Not sure whether and how you are affected? Ask a question about this vulnerability

Metrics

7.8

Priority

XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

Source: NVD, CVSS v3

7.1

CVSS v3

Severity High on the scale from 0 to 10.

Source: SUSE, Ubuntu, Red Hat, Siemens ProductCERT, BSI, CVE.org, Msrc Update Guide

0.4 %

EPSS score

Low — model estimates < 1% exploitation likelihood.

Source: FIRST EPSS, percentile 35.4

Show all metrics

Severity: High
Priority (0–325) The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first? Read in glossary: 63.83 Methodology
Exploit maturity An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack. Read in glossary: PoC (publicly reported)
XIEM Effective CVSS XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command. Read in glossary: 7.8 Methodology
CVSS v3 CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions. Read in glossary: 7.1
EPSS score The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“. Read in glossary: 0.4 %; Low — model estimates < 1% exploitation likelihood.
EPSS percentile The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking. Read in glossary: 35.4; Elevated — this CVE ranks above at least 10% of all CVEs scored today.
KEV status The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching. Read in glossary: —
Published: 01.06.2026

Detection rules

No NEOSEC detection rule is available for this vulnerability yet.

Classification under NIS2 and CRA

Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

NIS2 NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management. Read in glossary: High technical severity: assess and remediate the vulnerability in vulnerability handling under Art. 21(2)(e) NIS2 and document the decision.
CRA The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates. Read in glossary: From 11.12.2027, Annex I Part II CRA requires manufacturers of affected products with digital elements to handle vulnerabilities without delay and provide security updates.
ISO/IEC 27001 ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security. Read in glossary: Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

Description

Source: suse_csaf, Ubuntu Security Notices, redhat_csaf, siemens_advisory, BSI WID Portal, BSI CSAF, cvelistv5, Microsoft Security Update Guide, NVD (NIST), CVE.org (MITRE)

Affected products

The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

Affected products
		Affected versions	Fixed in
Linux	Linux	`5.16 – < 6.1.175` `6.19 – < 7.0.11` `2.6.24 – < 5.10.258` `6.13 – < 6.18.34` `5.11 – < 5.15.209` `—` `6.7 – < 6.12.92` `6.2 – < 6.6.142`	`6.1.175` `7.0.11` `5.10.258` `6.18.34` `5.15.209` `7.1` `6.12.92` `6.6.142`
Siemens	SIMATIC S7	`1500 TM MFP V1.1.1 GNU/Linux subsystem`	—

Vendors and products

Affected operating systems

Affected operating systems

Linux	ubuntu	linux-oracle-7.0	`noble`
Linux	linux	linux_kernel	`2.6.24`
Linux	linux	linux_kernel	`7.1`
Linux	linux	linux_kernel	—

Public exploit references

Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

Public exploit references

Reference tagged as exploit	github.com (opens in a new tab)	PoC (publicly reported)reported, not verified	—
PoC-in-GitHub (nomi-sec)	CVE-2026-46243 (opens in a new tab)github.com	PoC (publicly reported)reported, not verified	04.08.2026
PoC-in-GitHub (nomi-sec)	cifswitch (opens in a new tab)github.com	PoC (publicly reported)reported, not verified	30.05.2026
PoC-in-GitHub (nomi-sec)	CIFSwitch-go (opens in a new tab)github.com	PoC (publicly reported)reported, not verified	01.06.2026
PoC-in-GitHub (nomi-sec)	cifswitch-check (opens in a new tab)github.com	PoC (publicly reported)reported, not verified	03.06.2026
PoC-in-GitHub (nomi-sec)	CIFSwitch-Checker-CVE-2026-46243 (opens in a new tab)github.com	PoC (publicly reported)reported, not verified	02.06.2026

References & sources

git.kernel.orgstable/c/7713bd320ed4fc3d08a227cd8e41242219a16981
git.kernel.orgstable/c/9544559e59438a4b609b2fdfa0763d8360572824
git.kernel.orgstable/c/cf20038657d6d4974349556a34e08fe0490bebbc
git.kernel.orgstable/c/2035acfb17221729b1b8ac335e941868a04ca079
git.kernel.orgstable/c/a3bbda6502a9398b816fa2e71c9a3f955f58013d
git.kernel.orgstable/c/91f89c1d83e80417629791fcef6af8140d7d01c8
git.kernel.orgstable/c/0aece6685fc80a8de492688ca2315fb86ec379c7
git.kernel.orgstable/c/3da1fdf4efbc490041eb4f836bf596201203f8f2
github.commanizada/CIFSwitchExploit
openwall.comlists/oss-security/2026/06/01/6
access.redhat.comsecurity/cve/CVE-2026-46243Vulnerability database, x_refsource_REDHAT
bugzilla.redhat.comRHBZ#2481486Issue tracking, x_refsource_REDHAT
security.access.redhat.comdata/csaf/v2/vex/2026/cve-2026-46243.jsonx_sadp-csaf-vex
access.redhat.comerrata/RHSA-2026:23395Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:33486Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:27719Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:27729Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:41236Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:34048Vendor advisory, x_refsource_REDHAT
access.redhat.comerrata/RHSA-2026:40021Vendor advisory, x_refsource_REDHAT

Changes to this CVE

Who changed this CVE and when: NVD (analysis, affected products, CVSS), the CVE publisher (CNA) and additional providers such as CISA (ADP).

15.10.2026Record modifiedLinux

New references:

and 4 more references

Show 24 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://git.kernel.org/stable/c/0aece6685fc80a8de492688ca2315fb86ec379c7
Reference	added	—	https://git.kernel.org/stable/c/2035acfb17221729b1b8ac335e941868a04ca079
Reference	added	—	https://git.kernel.org/stable/c/3da1fdf4efbc490041eb4f836bf596201203f8f2
Reference	added	—	https://git.kernel.org/stable/c/7713bd320ed4fc3d08a227cd8e41242219a16981
Reference	added	—	https://git.kernel.org/stable/c/91f89c1d83e80417629791fcef6af8140d7d01c8
Reference	added	—	https://git.kernel.org/stable/c/9544559e59438a4b609b2fdfa0763d8360572824
Reference	added	—	https://git.kernel.org/stable/c/a3bbda6502a9398b816fa2e71c9a3f955f58013d
Reference	added	—	https://git.kernel.org/stable/c/cf20038657d6d4974349556a34e08fe0490bebbc
Reference	removed	https://git.kernel.org/stable/c/0aece6685fc80a8de492688ca2315fb86ec379c7	—
Reference	removed	https://git.kernel.org/stable/c/2035acfb17221729b1b8ac335e941868a04ca079	—
Reference	removed	https://git.kernel.org/stable/c/3da1fdf4efbc490041eb4f836bf596201203f8f2	—
Reference	removed	https://git.kernel.org/stable/c/7713bd320ed4fc3d08a227cd8e41242219a16981	—
Reference	removed	https://git.kernel.org/stable/c/91f89c1d83e80417629791fcef6af8140d7d01c8	—
Reference	removed	https://git.kernel.org/stable/c/9544559e59438a4b609b2fdfa0763d8360572824	—
Reference	removed	https://git.kernel.org/stable/c/a3bbda6502a9398b816fa2e71c9a3f955f58013d	—
Reference	removed	https://git.kernel.org/stable/c/cf20038657d6d4974349556a34e08fe0490bebbc	—
Reference type	removed	https://git.kernel.org/stable/c/0aece6685fc80a8de492688ca2315fb86ec379c7 Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/2035acfb17221729b1b8ac335e941868a04ca079 Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/3da1fdf4efbc490041eb4f836bf596201203f8f2 Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/7713bd320ed4fc3d08a227cd8e41242219a16981 Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/91f89c1d83e80417629791fcef6af8140d7d01c8 Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/9544559e59438a4b609b2fdfa0763d8360572824 Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/a3bbda6502a9398b816fa2e71c9a3f955f58013d Types: Patch	—
Reference type	removed	https://git.kernel.org/stable/c/cf20038657d6d4974349556a34e08fe0490bebbc Types: Patch	—

Source identifier: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

15.10.2026Record modifiedCISA ADP

New references:

https://github.com/manizada/CIFSwitch

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://github.com/manizada/CIFSwitch
Reference	removed	https://github.com/manizada/CIFSwitch	—
Reference type	removed	https://github.com/manizada/CIFSwitch Types: Third Party Advisory	—

Source identifier: 134c704f-9b21-4f2e-91b3-4a467353bcc0

15.10.2026Record modifiedCVE Program

New references:

http://www.openwall.com/lists/oss-security/2026/06/01/6

Show 3 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	http://www.openwall.com/lists/oss-security/2026/06/01/6
Reference	removed	http://www.openwall.com/lists/oss-security/2026/06/01/6	—
Reference type	removed	http://www.openwall.com/lists/oss-security/2026/06/01/6 Types: Mailing List, Third Party Advisory	—

Source identifier: af854a3a-2127-422b-91ae-364da2661108

15.10.2026Record modifiedRed Hat ADP

New references:

and 8 more references

Show 74 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:23258
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:23259
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:23329
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:23395
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:24381
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:25908
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:26462
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:26515
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:26535
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:26563
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:26570
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:27708
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:27719
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:27729
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:27735
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:28887
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:28962
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33219
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33220
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33221
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33222
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33223
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33224
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33225
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:33486
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:34048
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:34757
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:34764
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:34788
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:34815
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:36620
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:40021
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:41236
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:47727
Reference	added	—	https://access.redhat.com/security/cve/CVE-2026-46243
Reference	added	—	https://bugzilla.redhat.com/show_bug.cgi?id=2481486
Reference	added	—	https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46243.json
Reference	removed	https://access.redhat.com/errata/RHSA-2026:23258	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:23259	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:23329	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:23395	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:24381	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:25908	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:26462	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:26515	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:26535	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:26563	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:26570	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:27708	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:27719	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:27729	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:27735	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:28887	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:28962	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33219	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33220	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33221	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33222	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33223	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33224	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33225	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:33486	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:34048	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:34757	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:34764	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:34788	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:34815	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:36620	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:40021	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:41236	—
Reference	removed	https://access.redhat.com/errata/RHSA-2026:47727	—
Reference	removed	https://access.redhat.com/security/cve/CVE-2026-46243	—
Reference	removed	https://bugzilla.redhat.com/show_bug.cgi?id=2481486	—
Reference	removed	https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-46243.json	—

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

15.10.2026Record modifiedSiemens ADP

New references:

https://cert-portal.siemens.com/productcert/html/ssa-784472.html

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	added	—	New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/46xxx/CVE-2026-46243.json">CVE-2026-46243</a>
Reference	added	—	https://cert-portal.siemens.com/productcert/html/ssa-784472.html

Source identifier: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e

Show 3 older changes

23.07.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:40021

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:40021
Affected versions (publisher)	changed	NVIDIA for RHEL 10, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10 (+31)	NVIDIA for RHEL 10, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10 (+32)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

20.07.2026Record modifiedRed Hat ADP

New references:

https://access.redhat.com/errata/RHSA-2026:41236

Show 2 original changes

Individual changes of this event as published by NVD
Type	Action	Before	After
Reference	added	—	https://access.redhat.com/errata/RHSA-2026:41236
Affected versions (publisher)	changed	NVIDIA for RHEL 10, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10 (+29)	NVIDIA for RHEL 10, Red Hat Enterprise Linux 10, Red Hat Enterprise Linux 10 (+31)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

06.07.2026Record modifiedRed Hat ADP

1 individual change: Affected versions (publisher)

Show the original change

Individual changes of this event as published by NVD
Type	Action	Before	After
Affected versions (publisher)	changed	NVIDIA for RHEL 10, Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION), Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION) (+43)	NVIDIA for RHEL 10, Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION), Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION) (+42)

Source identifier: 0b0ca135-0b70-47e7-9f44-1890c2a1c46c

One NVD translation into another language is hidden.

Linked advisories

@RISK®: The Consensus Security Vulnerability Alert: Vol. 26, Num. 25SANS @RISK25.06.2026

Embed badge

Show the severity and KEV status of this vulnerability on your site – with a link back here. The image is updated hourly.

<a href="https://intel.neosec.eu/en/cve/CVE-2026-46243"><img src="https://intel.neosec.eu/badge/cve/CVE-2026-46243.svg?lang=en" alt="CVE-2026-46243 – NEOSEC Intel" height="20"></a>