Security readout for executives and security teams
Plain-English summary
CVE-2023-32257 is a Linux kernel ksmbd SMB server flaw that can let a remote attacker run code in kernel context. The source bundle rates it high severity with CVSS 8.1. Exposure appears narrow: Linux kernel 6.4-rc1 with ksmbd enabled and reachable. Red Hat lists RHEL 6, 7, 8, 9, and Fedora kernel packages as unaffected.
Executive priority
Treat this as high priority where ksmbd is enabled and reachable from untrusted networks. For standard Red Hat Enterprise Linux and Fedora environments listed as unaffected, priority is verification rather than emergency patching. The key business task is exposure discovery, not broad panic remediation.
Technical view
The flaw is a race condition in ksmbd processing of SMB2_SESSION_SETUP and SMB2_LOGOFF. Missing locking around an object can lead to kernel-context code execution. The CVSS vector is AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H, indicating network reachability, high attack complexity, no privileges, no user interaction, and full impact if exploited.
Likely exposure
Most exposure is likely limited to systems running the in-kernel ksmbd SMB server on Linux kernel 6.4-rc1. Systems using Samba user-space SMB are not identified as affected in the supplied sources. Red Hat Enterprise Linux 6 through 9 and Fedora kernel packages are listed as unaffected.
Exploitation context
The bundle does not show CISA KEV listing or other evidence of active exploitation. The vulnerability is remotely reachable over SMB when ksmbd is exposed, but CVSS marks attack complexity high, consistent with a race-condition bug that may be difficult to exploit reliably.
Researcher notes
The source data identifies CWE-362 and a race between SMB2 session setup and logoff handling in ksmbd. It does not provide exploit details, proof of exploitation, or a named fixed version beyond affected kernel 6.4-rc1 and Red Hat/Fedora unaffected statements.
Mitigation direction
- Inventory Linux hosts for ksmbd use and kernel version 6.4-rc1 exposure.
- Check vendor advisories for fixed kernel guidance before making patch claims.
- Disable ksmbd where it is not required for business operations.
- Restrict SMB access to trusted networks and hosts only.
- Prioritize remediation for externally reachable or untrusted-network SMB services.
Validation and detection
- Confirm whether ksmbd is enabled on Linux servers providing SMB service.
- Identify kernels matching 6.4-rc1 or vendor builds carrying this code.
- Verify Red Hat systems against Red Hat’s unaffected status and errata guidance.
- Review firewall and segmentation rules for SMB exposure.
- Document any NetApp relevance from the linked advisory before scoping products.
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-362: 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2023-32257 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
- High
- CVSS
- 8.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/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:H/PR:N/UI:N/S:U/C:H/I:H/A:H2.25.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
8.1HighVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://access.redhat.com/security/cve/CVE-2023-32257CVE reference · vdb-entry, x_refsource_REDHAT
- RHBZ#2219806CVE reference · issue-tracking, x_refsource_REDHAT
- https://security.netapp.com/advisory/ntap-20230915-0011/CVE reference
- https://www.zerodayinitiative.com/advisories/ZDI-CAN-20596/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.
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')
Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.