Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
CVE-2026-55009 is listed in the HOL Guard supply-chain feed, but affected software is not mapped to a package. Review the upstream advisory for the affected product and vendor guidance. Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
Reported by NVD (nvd).
Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
Review the upstream advisory, identify the affected product in your inventory, and apply the vendor update when one is available.
CVE-2026-55009 is listed in the HOL Guard supply-chain feed, but affected software is not mapped to a package. Review the upstream advisory for the affected product and vendor guidance. Deserialization of untrusted data in Microsoft Exchange Server allows an authorized attacker to elevate privileges locally.
Affected software not mapped. Review the upstream record for vendor-specific product and version guidance.
Reported by NVD (nvd).
HOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
Explore HOL GuardHOL Guard can help your team monitor supply-chain activity while the upstream record is clarified.
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