CVE-2026-55009
An attacker can exploit multiple vulnerabilities in Microsoft Exchange to execute arbitrary code, gain elevated permissions, or conduct spoofing attacks.
CSIRTS triage
- What
- Multiple vulnerabilities in Microsoft Exchange can be exploited to execute arbitrary code and gain elevated permissions.
- Who is affected
- All deployments of Microsoft Exchange are affected.
- Urgency
- Remediation is high priority due to the potential for exploitation.
- Action
- Install the latest security patches for Microsoft Exchange.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Moderate exploitation risk1.6% 30-day exploitation probability. Patch within normal cadence, watch for KEV listing. Riskier than 74% of all EPSS-scored CVEs.
Advisory coverage (5)
- high[NEW] [high] Microsoft Exchange: Multiple vulnerabilitiescert-bund · 2026-07-15
- unknownMultiple vulnerabilities in Microsoft products (July 15, 2026)cert-fr-avis · 2026-07-15
- unknownNCSC-2026-0234 [1.00] [M/H] Vulnerabilities fixed in Microsoft Exchangencsc-nl · 2026-07-14
- highCVE-2026-55009: Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker t…nvd · 2026-07-14
- highCVE-2026-55009: Microsoft Exchange Server Elevation of Privilege Vulnerabilitymsrc · 2026-07-14
External references
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