CVE-2026-26129

HIGHPre-NVD 7.57.5—Trending — 4 sources updated this week

7.5

Improper neutralization of special elements used in a command ('command injection') in M365 Copilot allows an unauthorized attacker to disclose information over a network.

CVSS v3: 7.5
EG Score: 7.5(high)
EPSS: 17.8%
KEV: Not listed

Published

May 7, 2026

Last Modified

June 2, 2026

Advisory Details (1)

Auto-updated May 7, 2026

Patch available. Sources: microsoft.

microsoft Patch Available

Security Update Guide - Microsoft Security Response Center

Security Update Guide - Microsoft Security Response Center. Patch available via Microsoft Security Update

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-26129

Vendor Advisories for CVE-2026-26129(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

CVE-2026-26129
Microsoft Security Response Center (MSRC)Critical
M365 Copilot Information Disclosure Vulnerability

Weakness Classification(1)

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

CWE-138

Data Freshness Timeline

(refreshed 20× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-04 13:16 UTCEG score recompute
2026-06-04 13:16 UTCVendor advisory
2026-06-04 13:16 UTCGHSA enrichment
2026-06-04 00:34 UTCEG score recompute
2026-06-04 00:34 UTCVendor advisory
2026-06-04 00:34 UTCGHSA enrichment
2026-06-03 11:51 UTCEG score recompute
2026-06-03 11:51 UTCVendor advisory
2026-06-03 11:51 UTCGHSA enrichment
2026-06-02 23:09 UTCEG score recompute
2026-06-02 23:09 UTCVendor advisory
2026-06-02 23:09 UTCGHSA enrichment
2026-06-02 20:13 UTCepss_batch
2026-06-02 20:13 UTCepss_batch
2026-06-02 10:26 UTCEG score recompute
2026-06-02 10:26 UTCVendor advisory
2026-06-02 10:26 UTCGHSA enrichment
2026-06-01 21:44 UTCEG score recompute
2026-06-01 21:44 UTCVendor advisory
2026-06-01 21:44 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-26129?

CVE-2026-26129 is a high vulnerability published on May 7, 2026. Improper neutralization of special elements used in a command ('command injection') in M365 Copilot allows an unauthorized attacker to disclose information over a network.

When was CVE-2026-26129 disclosed?

CVE-2026-26129 was first published in the National Vulnerability Database on May 7, 2026, with the most recent update on June 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2026-26129 actively exploited?

CVE-2026-26129 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 17.8% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.

What is the CVSS score of CVE-2026-26129?

CVE-2026-26129 has a CVSS v3 base score of 7.5 (NVD).

How do I remediate CVE-2026-26129?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-26129, 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

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-26129

Explore →

Is Your Infrastructure Affected by CVE-2026-26129?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs

CVE-2026-26129

📅 Published

🔄 Last Modified

📋 Advisory Details (1)