CVE-2026-48579: critical vulnerability in Microsoft Exchange Online
Microsoft Exchange Online Information Disclosure Vulnerability
Published · Updated
28Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 9.1epss 1.0%
exploitation probability
1.0%top 38% of all CVEs
observed exploitation
nono source reports it
Improper authorization in Microsoft Exchange Online allows an unauthorized attacker to disclose information over a network.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:U/RL:O/RC:C
Affected products
Microsoft · Microsoft Exchange OnlineRelated CVEs — Microsoft Exchange Online
In the same product, most dangerous first.
CVE-2026-65801CRITICALMicrosoft Exchange Online Elevation of Privilege VulnerabilityEPSS 0.9%CVE-2026-56191CRITICALMicrosoft Exchange Online Tampering VulnerabilityEPSS 0.9%CVE-2026-54998HIGHMicrosoft Exchange Online Elevation of Privilege VulnerabilityEPSS 0.8%CVE-2026-26137CRITICALMicrosoft Exchange Elevation of Privilege VulnerabilityEPSS 0.7%CVE-2026-48582CRITICALMicrosoft Exchange Online Elevation of Privilege VulnerabilityEPSS 0.7%