Security Resilience

CVE-2023-35368

Microsoft Exchange Server 2016 … 2019

Published
08 August 2023
Modified
10 August 2026
Patch / advisory
CVSS Score v3.1 8.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.025 84th percentile
Risk Priority 69 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-35368 is a high-severity Improper Input Validation (CWE-20) vulnerability in Microsoft Exchange Server. Its CVSS base score is 8.8 (High).

Operationally, ranked in the top 16% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Microsoft Exchange Remote Code Execution Vulnerability

CWE(s)

Related Threats

CVEs Like This One

CVE-2023-38181Same product: Microsoft Exchange Server
CVE-2025-59248Same product: Microsoft Exchange Server
CVE-2020-17144Same product: Microsoft Exchange Server
CVE-2023-21706Same product: Microsoft Exchange Server
CVE-2024-21410Same product: Microsoft Exchange Server
CVE-2021-31195Same product: Microsoft Exchange Server
CVE-2022-41082Same product: Microsoft Exchange Server
CVE-2021-34523Same product: Microsoft Exchange Server
CVE-2022-41040Same product: Microsoft Exchange Server
CVE-2021-33766Same product: Microsoft Exchange Server

Affected Assets

microsoft
exchange server
2016, 2019

Mitigating Controls

Likely Mitigating Controls AI

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-20

Security testing and developer training directly verify and enforce proper input validation, reducing exploitability of injection and malformed-data weaknesses.

addresses: CWE-20

Security testing and evaluation at multiple SDLC stages directly detects missing or flawed input validation, with the required remediation process ensuring fixes are applied.

addresses: CWE-20

Directly implements checks on information inputs to reject invalid data before processing.

addresses: CWE-20

Spam protection mechanisms perform filtering and detection on inbound/outbound messages, directly compensating for missing or weak input validation of unsolicited content.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

blocks

A.8.25 mandates security requirements, secure coding guidelines, checkpoints, testing (incl. code scans) and developer training in the SDLC, which reaches a slice of input validation defects but leaves the majority (incomplete enforcement, second-order inputs, parser differentials, post-validation canonicalization) unaddressed as in the SA-3 and A.8.28 anchors.

blocks

Mandating input controls that include integrity checks and input validation ensures that untrusted data is examined before use, blocking the root cause of many injection and malformed-data weaknesses.

blocks

Security-by-design principles explicitly call for data validation and sanitization at every layer, reducing the chance that malformed or malicious input will be processed without scrutiny.

prevents

Requiring language-specific secure coding standards, peer review, SAST and documented mitigation of common programming errors forces validation of all inputs before they are trusted.

finds

Testing against a defined set of requirements and using code review plus vulnerability scanning forces validation of inputs and handling of unanticipated conditions, reducing the chance that malformed data will be accepted.

Hardening callouts derived

DISA STIG baselines are authored against specific weaknesses. Where this CVE cites a broad weakness class, the mapping is not asserted at that abstraction (owner ruling, 2026-09-25: grade only at Base and below), so no rule is shown here rather than a rule shown against the wrong grain.

  • No fine-grained STIG row for CWE-20, a class-level weakness, and none of its children carries one either.

References