SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2020-1527

An elevation of privilege vulnerability exists when the Windows Custom Protocol Engine improperly handles memory.

HIGH 7.8EPSS 0.95%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.95%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

An elevation of privilege vulnerability exists when the Windows Custom Protocol Engine improperly handles memory. To exploit this vulnerability, an attacker would first have to gain execution on the victim system. An attacker could then run a specially crafted application to elevate privileges. The security update addresses the vulnerability by correcting how the Windows Custom Protocol Engine handles memory.

CVSS 3.1
7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS
0.95% probability · 61th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Affected
microsoft/windows 10 · microsoft/windows server 2016 · microsoft/windows server 2019
Source
secure@microsoft.com
EPSS trend
0%3%5%26 October 2026: 0.95%26 October 202626 October 2026

EPSS 0.9% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

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