Security Resilience

CVE-2023-35636

Info Disclosure in Microsoft Office 2016 … 2019

Published
12 December 2023
Modified
08 October 2026
Patch / advisory
CVSS Score v3.1 6.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS Score 0.18 97th percentile
Risk Priority 62 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-2023-35636 is a medium-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Microsoft Office. Its CVSS base score is 6.5 (Medium).

Operationally, ranked in the top 3% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

Microsoft Outlook contains an information disclosure vulnerability tracked as CVE-2023-35636. The flaw is rated 6.5 under CVSS 3.1 with the vector AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N and is associated with CWE-200. It affects the Microsoft Outlook client and permits exposure of sensitive information without requiring authentication.

An unauthenticated remote attacker can exploit the issue by sending a specially crafted message or link that a user must interact with, resulting in disclosure of confidential data from the victim's Outlook instance while leaving integrity and availability unaffected.

Microsoft has published remediation guidance in its Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2023-35636, which includes available updates and configuration recommendations for affected Outlook versions. The associated EPSS score has remained near 0.11 with only minor fluctuation between its recorded peak and current value.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Microsoft Outlook Information Disclosure Vulnerability

CWE(s)

Related Threats

CVEs Like This One

CVE-2024-43609Same product: Microsoft 365 Apps
CVE-2024-38200Same product: Microsoft 365 Apps
CVE-2024-38020Same product: Microsoft 365 Apps
CVE-2025-59240Same product: Microsoft 365 Apps
CVE-2023-36763Same product: Microsoft 365 Apps
CVE-2026-21260Same product: Microsoft 365 Apps
CVE-2023-21735Same product: Microsoft 365 Apps
CVE-2023-21738Same product: Microsoft 365 Apps
CVE-2023-21734Same product: Microsoft 365 Apps
CVE-2023-21741Same product: Microsoft 365 Apps

Affected Assets

microsoft
365 apps
all versions
microsoft
office
2016, 2019
microsoft
office long term servicing channel
2021

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-200

Automated marking applies security attributes to system outputs, making it harder for attackers to exploit unmarked sensitive information leading to unauthorized exposure.

addresses: CWE-200

Proper attribute retention and permitted-value enforcement limits unauthorized actors from accessing sensitive information lacking correct labels.

addresses: CWE-200

Prevents unauthorized exposure of sensitive information by prohibiting untrusted external systems from processing or storing it.

addresses: CWE-200

By enforcing authorization matching prior to sharing, the control reduces the risk of exposing sensitive information to unauthorized actors.

addresses: CWE-200

Review and removal of nonpublic information from publicly accessible systems directly prevents exposure of sensitive data to unauthorized actors.

addresses: CWE-200

Data mining protection mechanisms detect and block unauthorized bulk extraction of sensitive data, directly mitigating exposure to unauthorized actors.

addresses: CWE-200

Literacy training teaches users to recognize and avoid actions that result in unauthorized exposure of sensitive information.

addresses: CWE-200

Retaining and monitoring training records confirms personnel have completed privacy and security awareness training on handling sensitive data, reducing the chance of unauthorized exposure due to lack of knowledge.

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.5.10 only requires awareness, a topic-specific acceptable-use policy stating expected behaviours/monitoring, and procedures referencing classification and other controls; per the owner's explicit rule on labelling and similar dependency-style clauses, this does not itself prevent exposure (CWE-200) unless access/DLP/etc. act on it.

blocks

Requiring the return of all physical and electronic assets plus secure deletion of organizational data from personal devices reduces the chance that sensitive information remains accessible to departing personnel.

blocks

A.5.12 only defines and communicates a classification scheme so that protection needs can be understood; per the owner's explicit rule, labeling/classification does not itself prevent exposure and requires other controls (e.g. access enforcement) to act on it.

blocks

By requiring classification labels and metadata on all information assets, the control makes it harder for sensitive data to be inadvertently exposed because downstream systems and users can recognize and enforce handling rules based on those labels.

blocks

Requiring encryption, access controls, and recipient authentication for transfers directly reduces the chance that sensitive data reaches an unauthorized observer.

blocks

Secure delivery, protected storage, and confidentiality of allocation records limit exposure of authentication material to unauthorized observers.

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.

References