CYBERSECURITYTRACKER
Vulnerabilities

CVE-2021-26855

Microsoft Exchange Server: Server-Side Request Forgery

What it is

Reported

Microsoft Exchange Server contains an unspecified vulnerability that allows for remote code execution. This vulnerability is part of the ProxyLogon exploit chain.

Source reported · Source: NVD · Complete source description.
Dates
Source last published: · Source last updated:

What is affected

Reported

Microsoft; Exchange Server. Product-level identification only; no affected-version conclusion is available from this field.

Source reported · Source: NVD
Dates
Source last published: · Source last updated:

Urgency and basis

Tracker computed

Act now

Current priority score and EPSS: loading from the tracker record. They are read when this page loads and are not shown without JavaScript. They change daily and are not part of "Source last updated".

Tracker decision tier from the evidence detailed below
Dates
Source last updated:

Exploitation evidence

Reported

Active exploitation · CISA KEV · VulnCheck KEV · ENISA exploited-vulnerability catalog

Source reported
Dates
Active since: · CISA KEV added: · VulnCheck KEV added: · ENISA added: · Source last updated:

What to do

Reported

Apply updates per vendor instructions.

Source remediation ↗
Source reported · Tracked source remediation field
Dates
Source last updated:

Detection and validation

Mapped metadata availability only. These signals do not change priority.

Evidence detail

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Glossary

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