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3376 articles · 142290 vulns · 36/41 feeds (7d)
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7.5
CVE-2026-26129EXPLOITEDPATCHED
microsoft · 365_copilot_chat

M365 Copilot Information Disclosure Vulnerability

Description

Improper neutralization of special elements in M365 Copilot allows an unauthorized attacker to disclose information over a network.

Affected Products

VendorProductVersions
microsoft365_copilot_chat-

Also Affects

Downstream vendors/products affected by this vulnerability

VendorProductSourceConfidence
microsoft365 copilotcert_advisory90%

References

  • https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26129(vendor-advisory, patch)

Related News (3 articles)

Tier B
BSI Advisories3d ago
[NEU] [mittel] Microsoft 365 Copilot Business Chat: Mehrere Schwachstellen ermöglichen Offenlegung von Informationen
→ No new info (linked only)
Tier C
VulDB3d ago
CVE-2026-26129 | Microsoft 365 Copilots Business Chat special element
→ No new info (linked only)
Tier A
Microsoft MSRC4d ago
CVE-2026-26129 M365 Copilot Information Disclosure Vulnerability
→ No new info (linked only)
CVSS 3.17.5 HIGH
VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N/E:U/RL:O/RC:C
CISA KEV❌ No
Actively exploited✅ Yes
Patch available
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26129
CWECWE-138
PublishedMay 7, 2026
Last enriched3d agov3
Tags
managed service
Trending Score43
Source articles3
Independent3
Info Completeness10/14
Missing: epss, kev, iocs, mitre_attack

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Verification

State: verified
Confidence: 0%

Vulnerability Timeline

CVE Published
May 7, 2026
Discovered by ZDM
May 7, 2026
Updated: description, exploitAvailable, activelyExploited
May 7, 2026
Updated: tags
May 8, 2026
Actively Exploited
May 8, 2026
Exploit Available
May 8, 2026
Patch Available
May 8, 2026

Version History

v3
Last enriched 3d ago
v3Tier C3d ago

Updated description with more technical detail and marked patch availability as null due to managed service nature.

tags
via VulDB
v2Tier A4d ago

Added a detailed description of the vulnerability and marked it as actively exploited with an exploit available.

descriptionexploitAvailableactivelyExploited
via Microsoft MSRC
v14d ago

Initial creation