CVE-2026-55005
Microsoft Exchange Server 2016 CumulativVulnerabilityCVSS 8.8
Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over a network.
No public exploitation has been reported so far. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 3.1 : 8.8 HIGH
Attack vectorNetwork (remote)
Attack complexityLow
Privileges requiredLow
User interactionNone
ScopeUnchanged
Confidentiality impactHigh
Integrity impactHigh
Availability impactHigh
Vector: AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.