CVE-2026-31403
Vulnerability Scoring
Analysis In Progress
CVE-2026-31403 Vulnerability Analysis & Exploit Details
CVE-2026-31403
Attack Complexity Details
-
Attack Complexity:
Attack Complexity Analysis In Progress
-
Attack Vector:
Attack Vector Under Analysis
-
Privileges Required:
None
No authentication is required for exploitation.
-
Scope:
Impact is confined to the initially vulnerable component.
-
User Interaction:
None
No user interaction is necessary for exploitation.
CVE-2026-31403 Details
Status: Received on 03 Apr 2026, 16:16 UTC
Published on: 03 Apr 2026, 16:16 UTC
CVSS Release:
CVE-2026-31403 Vulnerability Summary
CVE-2026-31403: In the Linux kernel, the following vulnerability has been resolved: NFSD: Hold net reference for the lifetime of /proc/fs/nfs/exports fd The /proc/fs/nfs/exports proc entry is created at module init and persists for the module's lifetime. exports_proc_open() captures the caller's current network namespace and stores its svc_export_cache in seq->private, but takes no reference on the namespace. If the namespace is subsequently torn down (e.g. container destruction after the opener does setns() to a different namespace), nfsd_net_exit() calls nfsd_export_shutdown() which frees the cache. Subsequent reads on the still-open fd dereference the freed cache_detail, walking a freed hash table. Hold a reference on the struct net for the lifetime of the open file descriptor. This prevents nfsd_net_exit() from running -- and thus prevents nfsd_export_shutdown() from freeing the cache -- while any exports fd is open. cache_detail already stores its net pointer (cd->net, set by cache_create_net()), so exports_release() can retrieve it without additional per-file storage.
Assessing the Risk of CVE-2026-31403
Access Complexity Graph
The exploitability of CVE-2026-31403 depends on two key factors: attack complexity (the level of effort required to execute an exploit) and privileges required (the access level an attacker needs).
Exploitability Analysis for CVE-2026-31403
No exploitability data is available for CVE-2026-31403.
Understanding AC and PR
A lower complexity and fewer privilege requirements make exploitation easier. Security teams should evaluate these aspects to determine the urgency of mitigation strategies, such as patch management and access control policies.
Attack Complexity (AC) measures the difficulty in executing an exploit. A high AC means that specific conditions must be met, making an attack more challenging, while a low AC means the vulnerability can be exploited with minimal effort.
Privileges Required (PR) determine the level of system access necessary for an attack. Vulnerabilities requiring no privileges are more accessible to attackers, whereas high privilege requirements limit exploitation to authorized users with elevated access.
CVSS Score Breakdown Chart
Above is the CVSS Sub-score Breakdown for CVE-2026-31403, illustrating how Base, Impact, and Exploitability factors combine to form the overall severity rating. A higher sub-score typically indicates a more severe or easier-to-exploit vulnerability.
CIA Impact Analysis
Below is the Impact Analysis for CVE-2026-31403, showing how Confidentiality, Integrity, and Availability might be affected if the vulnerability is exploited. Higher values usually signal greater potential damage.
-
Confidentiality:
None
CVE-2026-31403 does not compromise confidentiality.
-
Integrity:
None
CVE-2026-31403 does not impact data integrity.
-
Availability:
None
CVE-2026-31403 does not affect system availability.
CVE-2026-31403 References
External References
- https://git.kernel.org/stable/c/6a8d70e2ad6aad2c345a5048edcb8168036f97d6
- https://git.kernel.org/stable/c/c7f406fb341d6747634b8b1fa5461656e5e56076
- https://git.kernel.org/stable/c/d1a19217995df9c7e4118f5a2820c5032fef2945
- https://git.kernel.org/stable/c/db4a9f99b12a7ee1c19d86c83a3b752c7effa6c6
- https://git.kernel.org/stable/c/e3d77f935639e6ae4b381c80464c31df998d61f4
- https://git.kernel.org/stable/c/e7fcf179b82d3a3730fd8615da01b087cc654d0b
CWE Common Weakness Enumeration
Unknown
Protect Your Infrastructure against CVE-2026-31403: Combat Critical CVE Threats
Stay updated with real-time CVE vulnerabilities and take action to secure your systems. Enhance your cybersecurity posture with the latest threat intelligence and mitigation techniques. Develop the skills necessary to defend against CVEs and secure critical infrastructures. Join the top cybersecurity professionals safeguarding today's infrastructures.
Other 5 Recently Published CVEs Vulnerabilities
- CVE-2026-5476 – A vulnerability was identified in NASA cFS up to 7.0.0 on 32-bit. Affected is the function CFE_TBL_ValidateCodecLoadSize of the file cfe/modules/tb...
- CVE-2026-5475 – A vulnerability was determined in NASA cFS up to 7.0.0. This impacts the function CFE_SB_TransmitMsg of the file cfe_sb_priv.c of the component CCS...
- CVE-2026-32186 – Microsoft Bing Elevation of Privilege Vulnerability
- CVE-2026-0545 – In mlflow/mlflow, the FastAPI job endpoints under `/ajax-api/3.0/jobs/*` are not protected by authentication or authorization when the `basic-auth`...
- CVE-2026-5474 – A vulnerability was found in NASA cFS up to 7.0.0. This affects the function CFE_MSG_GetSize of the file apps/to_lab/fsw/src/to_lab_passthru_encode...