Cyber Posture

CVE-2026-40357

HighRCE

Published: 12 May 2026

Published
12 May 2026
Modified
12 May 2026
KEV Added
Patch
CVSS Score 8.8 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS Score N/A
Risk Priority 18 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-40357 is a high-severity Deserialization of Untrusted Data (CWE-502) vulnerability. Its CVSS base score is 8.8 (High).

Operationally, it is not currently listed in the CISA KEV catalog.

Threat & Defense Details

Likely Mitigating ControlsAI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-502

Penetration testing supplies malicious serialized objects, detecting unsafe deserialization and supporting corrective actions.

addresses: CWE-502

Evaluation of untrusted data handling (deserialization testing) reveals unsafe processing, which the required remediation process addresses.

addresses: CWE-502

Untrusted serialized data can be deserialized and observed inside the chamber, blocking gadget-chain exploitation outside the sandbox.

addresses: CWE-502

Validates or rejects untrusted serialized data before deserialization occurs.

addresses: CWE-502

Identifies and blocks malicious code introduced through deserialization of untrusted data at system boundaries.

addresses: CWE-502

Integrity verification of serialized information can detect tampering before deserialization occurs.

addresses: CWE-502

Provenance of associated data allows detection of untrusted sources before deserialization or processing occurs.

NVD Description

Deserialization of untrusted data in Microsoft Office SharePoint allows an authorized attacker to execute code over a network.

Deeper analysisAI

Automated synthesis unavailable for this CVE.

Details

CWE(s)

References