HIGH
CVE-2026-21535
CWE-284Published: February 19, 2026· Updated: Feb 20, 2026
8.2
CVSS v3.1
EPSS:0.10%probability of exploitation in 30 daysPercentile:28.2th
Official Description
Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network.
Technical Analysis
CVE-2026-21535 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), with a CVSS base score of 8.2.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityLow
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N
Affected Vendors & Products
Microsoft1 product
teams
Source: NVD CPE · 1 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
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Official Patches & Advisories
All References (1)
Quick Facts
CVE IDCVE-2026-21535
CVSS Score8.2 / 10
SeverityHIGH
WeaknessCWE-284
CISA KEVNo
EPSS (30d)0.10%
Affected1 vendor
PublishedFeb 19, 2026
Related CVEs (CWE-284)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-21535 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.