CVE-2026-62915: Microsoft Exchange Server Security Feature Bypass Vulnerability

mediumCVSS 6.5CVE-2026-62915

Missing authorization in Microsoft Exchange Server allows an authorized attacker to bypass a security feature over a network.

CSIRTS triage

vendor: Microsoft product: Exchange Server Authentication bypass

What: Missing authorization checks in Microsoft Exchange Server allow authorized attackers to bypass security features.
Who is affected: Organizations running Exchange Server with authenticated users are affected.
Urgency: Medium severity (CVSS 6.5) requiring pre-existing authorization; patch according to normal cycles.
Action: Apply the latest Exchange Server security update addressing CVE-2026-62915.

AI-assisted analysis generated from the source advisory — verify against the original.

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Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 6.5
Published: 2026-08-11
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-62915

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-629150.48% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 40% of all EPSS-scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-62915	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

Recent advisories for Microsoft Exchange Server

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

high[NEW] [high] Microsoft Exchange Server: Multiple vulnerabilitiescert-bund · 2026-08-12
unknownNCSC-2026-0289 [1.00] [M/H] Vulnerabilities fixed in Microsoft Exchange Serverncsc-nl · 2026-08-12
mediumCVE-2026-65813: Server-side request forgery (ssrf) in Microsoft Exchange Server allows an authorized attacker …nvd · 2026-08-11
mediumCVE-2026-62915: Missing authorization in Microsoft Exchange Server allows an authorized attacker to bypass a s…nvd · 2026-08-11
highCVE-2026-62914: Improper neutralization of input during web page generation ('cross-site scripting') in Micros…nvd · 2026-08-11
highCVE-2026-62913: Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execu…nvd · 2026-08-11