Security readout for executives and security teams
Plain-English summary
CVE-2023-53427 is a Linux kernel CIFS/SMB3 client memory-safety flaw. Under a failed memory-registration allocation path, cleanup can touch freed memory. The source rates it high with CVSS 7.8, but the provided evidence indicates local, low-privilege exposure rather than remote unauthenticated exploitation.
Executive priority
Patch through normal high-priority kernel maintenance, with faster action for multi-user servers or systems where untrusted local users can trigger CIFS mounts. There is no provided evidence of active exploitation, so urgency is high but not emergency-level from these sources alone.
Technical view
The flaw is a CWE-416 use-after-free in Linux CIFS code. If MR allocation fails, MR recovery work is not initialized and the MR list is not cleared, leading to a warning and use-after-free during smbd_destroy in a mount.cifs SMB3 mount path.
Likely exposure
Exposure is most relevant on Linux systems running affected kernel versions with CIFS/SMB3 client functionality available. The CVSS vector is local, low privileges, no user interaction, with high confidentiality, integrity, and availability impact.
Exploitation context
The provided bundle does not show CISA KEV listing or active exploitation. Evidence is limited to kernel bug traces, affected version data, CVSS metadata, and stable kernel fix references. Treat exploitability as local and conditional on reaching the vulnerable CIFS mount path.
Researcher notes
Focus review on CIFS smbd MR allocation failure handling and smbd_destroy cleanup. The fix direction is to initialize MR recovery work before MR allocation and remove MRs from the list to prevent stale cleanup access.
Mitigation direction
- Apply vendor kernel updates containing the referenced CIFS fix.
- Prioritize systems that allow local users or services to perform CIFS mounts.
- Review distribution advisories for exact fixed kernel package versions.
- Limit CIFS mount capability where operationally unnecessary.
- Reboot into the fixed kernel after updating.
Validation and detection
- Inventory Linux kernel versions across servers and endpoints.
- Identify systems using CIFS or SMB3 client mounts.
- Compare installed kernels against vendor advisories and stable fix references.
- Confirm updated systems are running the remediated kernel after reboot.
- Monitor logs for CIFS mount failures or kernel memory-safety warnings.
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-416: 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-2023-53427 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/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.
SSVC decision data
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:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H1.85.9CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/stable/c/275a3d2b9408fc4895e342f772cab9a89960546eCVE reference, Linux
- https://git.kernel.org/stable/c/3524d6da0fe88aee79f06be6572955d16ad76b39CVE reference, Linux
- https://git.kernel.org/stable/c/cfd85a0922c4696d768965e686ad805a58d9d834CVE reference, Linux
- https://git.kernel.org/stable/c/7cbd5bdb5bd4404a5da4309521134b42c65846c0CVE reference, Linux
- https://git.kernel.org/stable/c/41832c62a75dad530dc5a2856c92ae5459d497e5CVE reference, Linux
- https://git.kernel.org/stable/c/2d0c4f5f618f58eba03385363717703bee873c64CVE reference, Linux
- https://git.kernel.org/stable/c/3e161c2791f8e661eed24a2c624087084d910215CVE reference, Linux
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.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.