Security Resilience

CVE-2023-21715

Access Control in Microsoft 365 Apps

CISA KEVActive ExploitationEUVD ExploitedAccess Control
Published
14 February 2023
Modified
19 August 2026
KEV Added
14 February 2023
Patch / advisory
CVSS Score v3.1 7.3
Click a component to see what it means
Raw vectorCVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
EPSS Score 0.12 96th percentile
Risk Priority 80 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-2023-21715 is a high-severity Incorrect Authorization (CWE-863) vulnerability in Microsoft 365 Apps. Its CVSS base score is 7.3 (High).

Operationally, ranked in the top 4% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities 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.

CVE-2023-21715 is a security feature bypass vulnerability in Microsoft Publisher, tracked under CWE-863 for incorrect authorization. It carries a CVSS 3.1 score of 7.3 with an attack vector that is local, low complexity, low privileges, and requires user interaction, resulting in high impact to confidentiality, integrity, and availability.

An attacker with local access and limited privileges can exploit the flaw after a user interacts with a crafted Publisher document, bypassing intended security controls to achieve full compromise of the affected system.

Microsoft has published remediation guidance through its Security Response Center update guide, and the vulnerability appears in CISA's catalog of known exploited vulnerabilities.

EPSS for the issue rose from a low baseline to a peak of 0.0151 on 2023-03-07 before receding, indicating a temporary increase in observed exploitation interest following public disclosure.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Microsoft Publisher Security Feature Bypass Vulnerability

CWE(s)
KEV Date Added
14 February 2023

Related Threats

CVEs Like This One

CVE-2023-24880Same vendor: Microsoftboth on KEV
CVE-2022-41091Same vendor: Microsoftboth on KEV
CVE-2023-23397Same product: Microsoft 365 Appsboth on KEV
CVE-2021-38646Same product: Microsoft 365 Appsboth on KEV
CVE-2021-42292Same product: Microsoft 365 Appsboth on KEV
CVE-2013-2551Same vendor: Microsoftboth on KEV
CVE-2004-0210Same vendor: Microsoftboth on KEV
CVE-2016-3393Same vendor: Microsoftboth on KEV
CVE-2015-2360Same vendor: Microsoftboth on KEV
CVE-2009-1123Same vendor: Microsoftboth on KEV

Affected Assets

microsoft
365 apps
all versions

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-863

Periodic review and update of procedures reduces incorrect authorization implementations over time.

addresses: CWE-863

Supervision identifies cases where authorization logic incorrectly permits unauthorized actions.

addresses: CWE-863

Defining permitted attribute values and auditing modifications reduces the chance of incorrect authorization outcomes due to tampered or missing labels.

addresses: CWE-863

The authorization process and usage restrictions help prevent incorrect authorization for remote access types.

addresses: CWE-863

Establishing configuration and connection requirements helps ensure correct rather than incorrect authorization for wireless access.

addresses: CWE-863

Establishing connection authorization processes for mobile devices helps ensure authorization decisions are correctly implemented rather than incorrect.

addresses: CWE-863

Monitoring account use, notifying on changes, and reviewing accounts for compliance corrects incorrect authorization assignments.

addresses: CWE-863

Ensures authorization decisions for external system use are correctly implemented and enforced.

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

Requiring consistency between access rights and classification plus formal approval steps ensures that the authorization logic correctly distinguishes between entities that should and should not be granted access.

blocks

A.5.18's provisioning, revocation, review and adjustment of access rights (incl. before role changes/termination, with segregation and owner approval) directly stops incorrect authorization decisions from being exploitable in the vast majority of cases; the bounded remainder is incorrectness inside the authorization logic itself (e.g. flawed conditional or missing check) rather than rights that were wrongly granted.

blocks

A.8.3 directly mandates restricting access to information per policies via configuration, identity/group controls, isolation, and dynamic techniques that enforce correct authorization decisions, addressing most but not all slices of CWE-863 (e.g., remainder in non-access-decision authorization errors like timing or environmental factors).

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-863, a class-level weakness, and none of its children carries one either.

References