Security readout for executives and security teams
Plain-English summary
CVE-2023-6535 is a Linux kernel NVMe over TCP flaw that can crash affected systems. For exposed storage infrastructure, the business impact is availability loss, not data theft. Red Hat rates it medium, but systems relying on NVMe/TCP for production storage should treat remediation as operationally important.
Executive priority
Treat as a scheduled but prioritized availability fix, especially for storage-dependent production systems. It is not documented here as exploited in the wild, but a successful attack can crash affected hosts and interrupt services.
Technical view
The flaw is a NULL pointer dereference in the Linux kernel NVMe driver, specifically nvmet_tcp_execute_request. Crafted TCP packets against NVMe over TCP can trigger a kernel panic and denial of service. The source bundle lists affected Red Hat kernels and related RHEL, EUS, RHV, and RHOL packages.
Likely exposure
Exposure is most likely where affected Red Hat kernel packages run NVMe over TCP services or related storage paths. General Linux hosts are lower concern if NVMe/TCP is not enabled or reachable. The affected list is Red Hat-focused and should not be expanded beyond the provided sources.
Exploitation context
The bundle says KEV is false and provides no cited evidence of active exploitation. The description says unauthenticated crafted TCP packets, while the CVSS vector records PR:L, so access requirements should be verified against Red Hat guidance before final risk scoring.
Researcher notes
Key uncertainty is the access requirement: the narrative says unauthenticated, but CVSS uses PR:L. Analysis should preserve that discrepancy. Avoid broad Linux impact claims unless supported by vendor data; the supplied affected inventory is Red Hat-specific.
Mitigation direction
- Identify affected Red Hat kernel, kernel-rt, RHV, EUS, and RHOL package versions.
- Prioritize systems using or exposing NVMe over TCP.
- Apply the relevant Red Hat RHSA security updates after normal testing.
- Check vendor advisories for any supported temporary mitigations.
- Schedule reboot or kernel activation steps required by the vendor update path.
Validation and detection
- Confirm installed kernel or package versions against the affected version list.
- Verify whether NVMe over TCP is enabled or reachable on production systems.
- Confirm the relevant RHSA update is installed and active after reboot.
- Review logs for kernel panic or storage-service disruption symptoms.
- Document systems where vendor guidance is unavailable or evidence is incomplete.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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-476: 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.
Open ATT&CK lookupCVE-2023-6535 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
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.
CVSS vector scores
1 official scoreWe 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.
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H2.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- RHSA-2024:0723CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:0724CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:0725CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:0881CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:0897CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:1248CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:2094CVE reference · vendor-advisory, x_refsource_REDHAT
- RHSA-2024:3810CVE reference · vendor-advisory, x_refsource_REDHAT
- https://access.redhat.com/security/cve/CVE-2023-6535CVE reference · vdb-entry, x_refsource_REDHAT
- RHBZ#2254053CVE reference · issue-tracking, x_refsource_REDHAT
- https://lists.debian.org/debian-lts-announce/2024/06/msg00016.htmlCVE reference · x_transferred
- https://security.netapp.com/advisory/ntap-20240415-0003/CVE reference · x_transferred
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZFYW6R64GPLUOXSQBJI3JBUX3HGLAYPP/CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
NULL Pointer Dereference
NULL Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.