gcdRadar
archive/Patch now/AIR-2026-0946
closedclosed 22 Jan 2026Patch now2 Disclosed vulnerabilityAI

CVE-2026-21520: Microsoft Copilot Studio Information Disclosure

Copilot Studio

An unauthorized information exposure vulnerability in Microsoft Copilot Studio permits unauthenticated attackers to view sensitive data. The vulnerability is exploitable via a network attack vector.

disclosed CVENo confirmed exploitation, so this record is tracked as a disclosed vulnerability and not counted as an incident. It moves into the counts if CISA or the vendor confirms exploitation. Why

CVSS
7.5
EPSS
0.02 · top 25% · 2026-11-13
EPSS scores by FIRST
fix status
Fix status unknown
first report
22 Jan 2026
last update
22 Jan 2026
CVE ids
CVE-2026-21520other records

Timeline · 1

  1. 22 Jan 2026CVE-2026-21520: Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive…

Sources · 1

Advisories and databases

  1. 2026-01-22
    CVE-2026-21520: Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive…
    NVD · nvd.nist.gov/vuln/detail/CVE-2026-21520

Titles and links belong to their publishers. The summary above is written by gcdRadar in its own words; data is CC BY-SA 4.0.

Classification

lane
Patch now
AI role
Attack on AI
categories
Infrastructure vulnerabilityData leak
severity
2 · Disclosed vulnerability
fix status
Fix status unknown
targets
Microsoft
owasp llm top 10
LLM02:2025 Sensitive Information DisclosureLLM03:2025 Supply Chain
mitre atlas
no technique for these categories
tags
information-disclosure
dates
happened 22 Jan 2026 · first reported 22 Jan 2026
origin
NVD
Vulnerability record from NVD / the GitHub Advisory Database. This product uses the NVD API but is not endorsed or certified by the NVD.
record
confidence 0.95 · created 2026-10-18 10:04Z · updated 2026-10-18 10:04Z

Lane, AI role, categories and severity come from the classifier; the OWASP and ATLAS rows are derived from the categories. How these are assigned

Copy a brief

This record as a short Markdown brief, for a ticket, a chat or a coding agent.

the brief as text
# CVE-2026-21520: Microsoft Copilot Studio Information Disclosure

https://gcdradar.vercel.app/incidents/cve-2026-21520-microsoft-copilot-studio-information-disclosu · AIR-2026-0946 · closed 2026-01-22

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-01-22
- AI role: Attack on AI
- Products: Copilot Studio
- CVE ids: CVE-2026-21520
- CVSS: 7.5

## Summary

An unauthorized information exposure vulnerability in Microsoft Copilot Studio permits unauthenticated attackers to view sensitive data. The vulnerability is exploitable via a network attack vector.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-01-22: CVE-2026-21520: Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive… (https://nvd.nist.gov/vuln/detail/CVE-2026-21520)

## Sources

- 2026-01-22 NVD: CVE-2026-21520: Exposure of Sensitive Information to an Unauthorized Actor in Copilot Studio allows a unauthenticated attacker to view sensitive… https://nvd.nist.gov/vuln/detail/CVE-2026-21520

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.

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