SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityAnalyzed

CVE-2020-17144

Microsoft Exchange Server Remote Code Execution Vulnerability

KEVHIGH 8.4EPSS 36.5%

Does this matter?

Known to be exploited in the wild (CISA KEV, CISA remediation deadline 3 May 2022). Treat as an emergency change: patch or isolate now, then hunt for prior compromise.

Description

Microsoft Exchange Remote Code Execution Vulnerability

CVSS 3.1
8.4 HIGHCVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:H
EPSS
36.51% probability · 98th percentile
Public exploits
None in Exploit-DB
CISA KEV
Listed 3 November 2021 · due 3 May 2022
Weakness
CWE-502
Affected
microsoft/exchange server
Source
secure@microsoft.com
EPSS trend
0%20%40%30 October 2026: 36.51%30 October 202630 October 2026

EPSS 36.5% since 30 October 2026; no change recorded yet. The dashed line is the ten per cent mark our analysts treat as “patch before the next change window”. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

CISA notes

Apply updates per vendor instructions. https://nvd.nist.gov/vuln/detail/CVE-2020-17144

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.