Home/CVE/In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.spnego descripti
CVE

CVE-2026-46243

In the Linux kernel, the following vulnerability has been resolved: smb: client: reject userspace cifs.spnego descripti

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. Only accept cifs.spnego descriptions while CIFS is using its private spnego_cred to request the key.

HIGH · CVSS 7.1 EPSS 0.00021
Act now
  • Public exploit or PoC is available
  • CVSS base score ≥ 7.0
Sigma rules0 YARA rules0
Look this up elsewhere - one-click external pivots
How to read a CVE - triage first, then detect and patch
This page is every public fact about CVE-2026-46243, cross-linked. Its job is to answer one question fast - does this need my attention now? - and then hand you the two things you do about it. Here is how an analyst reads it.
Triage: should I act now? Four signals, and they are not interchangeable:
CVSSseverity - how bad it is IF exploited, 0-10. A high CVSS alone is not urgency; a flaw can be a perfect 10 and never actually be attacked. EPSSprobability - a model’s estimate of the chance it is exploited in the next 30 days, 0-1. This is the “will it actually happen” signal. CISA KEVconfirmed - it is being exploited in the wild right now. The strongest signal on the page; KEV beats any score. Weaponisedavailability - public exploits / PoCs, and especially Metasploit modules rated Excellent / Great. Reliable, packaged exploit code means low-skill attackers can use it today.
How they combine: KEV, or a dependable Metasploit module, means patch now regardless of CVSS. High CVSS + low EPSS + no exploit is real but not an emergency - schedule it. Low CVSS but KEV-listed still gets patched now. The verdict above already weighed these for you; this is how it got there.
Then what - two workflows:
Detectwhen you cannot patch today, follow this CVE to the ATT&CK techniques it enables, then Build a SIEM detection (the green button) - author a rule, test it in Atomic, deploy it. That buys visibility while the patch waits. PatchAffected products / packages tell you if you are exposed; Fixed versions by distribution and Vendor advisories give the exact version that closes it.
Reading order for the panels below: verdict + badges, then Public exploits / Metasploit (is it weaponised), then ATT&CK techniques + Sigma / IDS rules (can I detect it), then Affected products / packages + Fixed versions (am I exposed, what patches it), then Threat actors / IOCs (who uses it), then Scoring & timeline / references (the evidence).

Weakness Classification

Public Exploits & PoCs

3
These PoC and exploit links come from public sources and are not verified to be safe or functional. Review the code before running anything, and treat unverified entries as untrusted.
📦

Fixed versions by distribution

80
The package version that resolves this CVE on each Linux distribution, from the vendor’s published security data. fixed in shows a patched version exists; open means the package is listed as affected with no fix yet.
oracle allbpftool fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel open
oracle allkernel-abi-stablelists open
oracle allkernel-core fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-cross-headers open
oracle allkernel-debug fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-debug-core open
oracle allkernel-debug-devel fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-debug-modules fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-debug-modules-extra fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-devel fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-headers fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-modules fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-modules-extra fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-tools fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-tools-libs fixed in 0:4.18.0-553.129.1.el8_10
oracle allkernel-tools-libs-devel open
oracle allperf fixed in 0:4.18.0-553.129.1.el8_10
oracle allpython3-perf fixed in 0:4.18.0-553.129.1.el8_10
rhel 8bpftool fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel-abi-stablelists open
rhel 8kernel-core fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel-debug fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel-debug-core open
rhel 8kernel-debug-devel fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel-debug-modules fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel-debug-modules-extra open
rhel 8kernel-devel open
rhel 8kernel-modules open
rhel 8kernel-modules-extra open
rhel 8kernel-rt open
rhel 8kernel-rt-core fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-debug fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-debug-core open
rhel 8kernel-rt-debug-devel fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-debug-kvm fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-debug-modules fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-debug-modules-extra fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-devel fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-kvm fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-modules fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-rt-modules-extra fixed in 0:4.18.0-553.129.1.rt7.470.el8_10
rhel 8kernel-tools open
rhel 8kernel-tools-libs fixed in 0:4.18.0-553.129.1.el8_10
rhel 8kernel-tools-libs-devel open
rhel 8kernel-zfcpdump open
rhel 8kernel-zfcpdump-core open
rhel 8kernel-zfcpdump-devel open
rhel 8kernel-zfcpdump-modules open
rhel 8kernel-zfcpdump-modules-extra open
rhel 8perf open
rhel 8python3-perf open
rhel 9kernel open
rhel 9kernel-64k open
rhel 9kernel-64k-core open
rhel 9kernel-64k-debug open
rhel 9kernel-64k-debug-core fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-64k-debug-devel open
rhel 9kernel-64k-debug-devel-matched open
rhel 9kernel-64k-debug-modules open
rhel 9kernel-64k-debug-modules-core open
rhel 9kernel-64k-debug-modules-extra fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-64k-devel open
rhel 9kernel-64k-devel-matched open
rhel 9kernel-64k-modules fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-64k-modules-core open
rhel 9kernel-64k-modules-extra fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-abi-stablelists open
rhel 9kernel-core fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-debug fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-debug-core fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-debug-devel fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-debug-devel-matched open
rhel 9kernel-debug-modules fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-debug-modules-core open
rhel 9kernel-debug-modules-extra fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-debug-uki-virt fixed in 0:5.14.0-687.13.1.el9_8
rhel 9kernel-devel open
rhel 9kernel-devel-matched open

Scoring & Timeline

7.1
HIGH · CVSS v3.1 · 416baaa9-dc9f-4396-8d5f-8c081fb06d67
View on NVD
Attack Vector
Network Adjacent Local Physical
Attack Complexity
Low High
Privileges Required
None Low High
User Interaction
None Required
Scope
Unchanged Changed
Confidentiality
None Low High
Integrity
None Low High
Availability
None Low High
Published to NVD01 Jun 2026 · 05:17 PM
CVSS VectorCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
SSVC triage · cisa-vulnrichment
Exploitation
poc
Automatable
no
Technical impact
total
SSVC asks the questions that actually drive patch urgency: is it being exploited, can attacks be automated, and how total is the impact.

Vendor Advisories

14
suse-csafSUSE-SU-2026:2383-1
suse-csafSUSE-SU-2026:2331-1
suse-csafSUSE-SU-2026:2332-1
suse-csafSUSE-SU-2026:2310-1
suse-csafSUSE-SU-2026:2317-1
SOC and Response
CVE triage
Stack monitoring
Am I affected
IOC triage
KEV catalog
Daily brief
Change tracking
Detection Engineering
Coverage workspace
Detection coverage
Coverage check
Telemetry ceiling
SIEM query builder
Sigma rules
SIEM rules
YARA rules
Network rules
D3FEND
Threat Hunting
Threat actors
ATT&CK techniques
Attack paths
Indicators
Atomic tests
Red Team and Pentest
Exploitability triage
Recon pack
Attack paths
CAPEC patterns
Adversary emulation
Compliance and GRC
Framework mapping
Control assessment
Audit view
Coverage report
Atlas Search Threat actors Techniques Tools & malware CWE CAPEC KEV catalog Package vulns TAXII feed Data sources
About All capabilities Pricing API docs Live statistics Live status Privacy policy Terms of service
threatengine.sh