CVE-2026-21535

HIGHNVD 7.58.2▲
EchelonGraph scoreMEDIUM confidence

Score 8.2 from GitHub Security Advisory (severity: HIGH) published 2026-02-20. NVD baseline CVSS 7.5; sources differ by 0.7.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 4 sources updated this week
8.2EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network.

CVSS v3
7.5
EG Score
8.2(medium)
EG Risk
42(Track)
EG Risk 42/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity82% × 45%
Exploitation1% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
45%
KEV
Not listed

Published

February 19, 2026

Last Modified

June 17, 2026

References (1)

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 5× in last 7d / 5× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-30 01:30 UTCEPSS rescore
  2. 2026-07-27 14:13 UTCEG score recompute
  3. 2026-07-27 14:13 UTCVendor advisory
  4. 2026-07-27 14:13 UTCGHSA enrichment
  5. 2026-07-27 14:13 UTCEPSS rescore

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-21535?
CVE-2026-21535 is a high vulnerability published on February 19, 2026. Improper access control in Microsoft Teams allows an unauthorized attacker to disclose information over a network.
When was CVE-2026-21535 disclosed?
CVE-2026-21535 was first published in the National Vulnerability Database on February 19, 2026, with the most recent update on June 17, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21535 actively exploited?
CVE-2026-21535 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 55.1% of all scored CVEs.
What is the CVSS score of CVE-2026-21535?
CVE-2026-21535 has a CVSS v3 base score of 7.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.2.
How do I remediate CVE-2026-21535?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-21535, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-21535

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