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CVE Record

CVE-2024-0646: Kernel: ktls overwrites readonly memory pages when using function splice with a ktls socket as destination

An out-of-bounds memory write flaw was found in the Linux kernel’s Transport Layer Security functionality in how a user calls a function splice with a ktls socket as the destination. This flaw allows a local user to crash or potentially escalate their privileges on the system.

HighCVSS 7Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

CVE-2024-0646 is a Linux kernel flaw in kernel TLS handling. A logged-in local user could crash the system or potentially gain higher privileges. This is not a remote internet attack based on the provided sources, but it matters for multi-user servers, shared hosting, and systems where untrusted users or workloads can run code.

Executive priority

Treat as a near-term patching priority for Linux servers with local users or untrusted workloads. It is high severity but not described as remotely exploitable or actively exploited in the provided sources.

Technical view

The flaw is an out-of-bounds write in Linux kernel kTLS when splice is used with a kTLS socket as the destination. Red Hat rates it High with CVSS 7.0: local attack vector, low privileges required, high attack complexity, and potential high confidentiality, integrity, and availability impact.

Likely exposure

Exposure is most relevant to affected Red Hat Enterprise Linux 8 and 9 kernel or kernel-rt packages listed in Red Hat advisories. Systems are more exposed when local shell users, containers, or application workloads can execute code on the host. The provided data does not establish exposure for other Linux distributions.

Exploitation context

The provided sources do not show CISA KEV listing or confirmed active exploitation. Exploitation requires local access and has high attack complexity. Practical risk increases where attackers may already have low-privileged access and seek denial of service or privilege escalation.

Researcher notes

Key constraints are AV:L, PR:L, AC:H, and CWE-787. The affected path involves kTLS and splice behavior. Avoid assuming distribution-wide impact beyond the listed Red Hat products unless validated through each vendor’s advisory or kernel backport status.

Mitigation direction

  • Apply the relevant Red Hat kernel security errata for your RHEL stream.
  • Prioritize multi-user, container-hosting, and externally managed workload systems.
  • Reboot into the updated kernel after applying kernel packages.
  • If patch timing is constrained, check Red Hat guidance for supported workarounds.

Validation and detection

  • Inventory RHEL 8 and RHEL 9 systems and installed kernel versions.
  • Compare installed kernel or kernel-rt packages against affected versions in the CVE data.
  • Confirm applicable RHSA updates are installed through standard package management reporting.
  • Verify systems are running the updated kernel after reboot.
  • Monitor vendor advisories for changes to affected status or mitigations.
Prepared
Confidence
high
Sources
12

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · low confidence lookup

CWE-787: Exact CWE lookup

Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

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cve · low confidence lookup

CVE-2024-0646 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

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Vulnerability profileCVE Program record
Severity
High
CVSS
7 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
5Timeline events
2ADP providers
27Source links

SSVC decision data

CISA-ADPCISA Coordinator
Timestamp
Version
2.0.3
Exploitation: noneAutomatable: noTechnical Impact: total

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
7CVSS 3.1HighCVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H15.9redhat

Vulnerability scoring details

Base CVSS 3.1 score

7High
CVSS 3.1 vector shape for CVE-2024-0646Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Vulnerability timeline

Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.

  1. Source timelineredhat

    Made public.

  2. Source timelineredhat

    Reported to Red Hat.

  3. CVE reservedCVE Program

    The CVE ID was reserved by the assigning CNA.

  4. CVE publishedCVE Program

    The CVE record was published.

  5. CVE updatedCVE Program

    The CVE record metadata indicates this as the latest update time.

ADP provider summaries

CVECVE Program Container
CISA-ADPCISA ADP Vulnrichment
other:ssvc

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
Unknown vendorkernelkernel, 0unaffected
Red HatRed Hat Enterprise Linux 8kernel-rt, 0:4.18.0-513.18.1.rt7.320.el8_9affected
Red HatRed Hat Enterprise Linux 8kpatch-patchunaffected
Red HatRed Hat Enterprise Linux 8kernel, 0:4.18.0-513.18.1.el8_9affected
Red HatRed Hat Enterprise Linux 8.2 Advanced Update Supportkernel, 0:4.18.0-193.128.1.el8_2affected
Red HatRed Hat Enterprise Linux 8.2 Telecommunications Update Servicekernel-rt, 0:4.18.0-193.128.1.rt13.179.el8_2affected
Red HatRed Hat Enterprise Linux 8.2 Telecommunications Update Servicekernel, 0:4.18.0-193.128.1.el8_2affected
Red HatRed Hat Enterprise Linux 8.2 Update Services for SAP Solutionskernel, 0:4.18.0-193.128.1.el8_2affected
Red HatRed Hat Enterprise Linux 8.2 Update Services for SAP Solutionskpatch-patchunaffected
Red HatRed Hat Enterprise Linux 8.4 Advanced Mission Critical Update Supportkernel, 0:4.18.0-305.125.1.el8_4affected
Red HatRed Hat Enterprise Linux 8.4 Telecommunications Update Servicekernel-rt, 0:4.18.0-305.125.1.rt7.201.el8_4affected
Red HatRed Hat Enterprise Linux 8.4 Telecommunications Update Servicekernel, 0:4.18.0-305.125.1.el8_4affected
Red HatRed Hat Enterprise Linux 8.4 Update Services for SAP Solutionskernel, 0:4.18.0-305.125.1.el8_4affected
Red HatRed Hat Enterprise Linux 8.4 Update Services for SAP Solutionskpatch-patchunaffected
Red HatRed Hat Enterprise Linux 8.6 Extended Update Supportkernel, 0:4.18.0-372.91.1.el8_6affected
Red HatRed Hat Enterprise Linux 8.6 Extended Update Supportkpatch-patchunaffected
Red HatRed Hat Enterprise Linux 8.8 Extended Update Supportkpatch-patchunaffected
Red HatRed Hat Enterprise Linux 8.8 Extended Update Supportkernel, 0:4.18.0-477.51.1.el8_8affected
Red HatRed Hat Enterprise Linux 9kernel, 0:5.14.0-362.24.1.el9_3affected
Red HatRed Hat Enterprise Linux 9kernel, 0:5.14.0-362.24.1.el9_3affected
Red HatRed Hat Enterprise Linux 9kpatch-patchunaffected
Red HatRed Hat Enterprise Linux 9.0 Extended Update Supportkernel, 0:5.14.0-70.93.2.el9_0affected
Red HatRed Hat Enterprise Linux 9.0 Extended Update Supportkernel-rt, 0:5.14.0-70.93.1.rt21.165.el9_0affected
Red HatRed Hat Enterprise Linux 9.0 Extended Update Supportkpatch-patchunaffected
Red HatRed Hat Enterprise Linux 9.2 Extended Update Supportkernel, 0:5.14.0-284.52.1.el9_2affected
Red HatRed Hat Enterprise Linux 9.2 Extended Update Supportkernel-rt, 0:5.14.0-284.52.1.rt14.337.el9_2affected
Red HatRed Hat Enterprise Linux 9.2 Extended Update Supportkpatch-patchunaffected
Red HatRed Hat Virtualization 4 for Red Hat Enterprise Linux 8kernel, 0:4.18.0-372.91.1.el8_6affected
Red HatRHOL-5.8-RHEL-9openshift-logging/cluster-logging-operator-bundle, v5.8.6-22affected
Red HatRHOL-5.8-RHEL-9openshift-logging/cluster-logging-rhel9-operator, v5.8.6-11affected
Weakness

CWE details

CWE-787

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.