Cyber Posture

CVE-2025-59286

CriticalRCE

Published: 09 October 2025

Published
09 October 2025
Modified
11 December 2025
KEV Added
Patch
CVSS Score 9.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N
EPSS Score 0.0011 28.6th percentile
Risk Priority 19 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-59286 is a critical-severity Command Injection (CWE-77) vulnerability in Microsoft 365 Copilot Chat. Its CVSS base score is 9.3 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 28.6th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

SI-10 directly and comprehensively prevents command injection by validating and neutralizing special elements in inputs to Copilot.

prevent

SI-2 ensures timely remediation of the specific command injection flaw in CVE-2025-59286 through patching as advised by MSRC.

prevent

SI-9 restricts information inputs to Copilot, limiting opportunities for special elements that enable command injection.

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
Why these techniques?

Command injection in a network-accessible Copilot component directly enables remote exploitation of public-facing apps (T1190) and arbitrary command execution via interpreters (T1059).

Confidence: HIGH · MITRE ATT&CK Enterprise v18.1

NVD Description

Improper neutralization of special elements used in a command ('command injection') in Copilot allows an unauthorized attacker to disclose information over a network.

Deeper analysisAI

CVE-2025-59286 is a command injection vulnerability (CWE-77) in Copilot due to improper neutralization of special elements used in a command. Published on 2025-10-09, it carries a CVSS v3.1 base score of 9.3 (AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N), marking it as critical severity with network accessibility, low complexity, no privileges or user interaction required, changed scope, high confidentiality impact, low integrity impact, and no availability impact.

An unauthorized attacker can exploit this vulnerability over the network without authentication or user interaction. Successful exploitation allows disclosure of information, enabling remote data exfiltration with potential minor integrity alterations due to the command injection.

The Microsoft Security Response Center advisory at https://msrc.microsoft.com/update-guide/vulnerability/CVE-2025-59286 provides details on patches and mitigation recommendations.

Details

CWE(s)

Affected Products

microsoft
365 copilot chat
all versions

CVEs Like This One

CVE-2025-59272Same product: Microsoft 365 Copilot Chat
CVE-2025-53787Same product: Microsoft 365 Copilot Chat
CVE-2026-26137Same product: Microsoft 365 Copilot Chat
CVE-2025-59252Same vendor: Microsoft
CVE-2026-26129Same product: Microsoft 365 Copilot Chat
CVE-2026-21520Same vendor: Microsoft
CVE-2026-26164Same product: Microsoft 365 Copilot Chat
CVE-2026-32194Same vendor: Microsoft
CVE-2025-55227Same vendor: Microsoft
CVE-2025-24049Same vendor: Microsoft

References