SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2017-20190

Some Microsoft technologies as used in Windows 8 through 11 allow a temporary client-side performance degradation during processing of multiple Unicode combining characters, aka a "Zalgo text" attack.

UnscoredEPSS 0.26%

Does this matter?

Not yet scored. NVD analysis is pending; check back once CVSS and EPSS values are published.

Description

Some Microsoft technologies as used in Windows 8 through 11 allow a temporary client-side performance degradation during processing of multiple Unicode combining characters, aka a "Zalgo text" attack. NOTE: third parties dispute whether the computational cost of interpreting Unicode data should be considered a vulnerability.

CVSS
Not yet scored
EPSS
0.26% probability · 18th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-176
Source
cve@mitre.org
EPSS trend
0%3%5%27 October 2026: 0.26%27 October 202627 October 2026

EPSS 0.3% since 27 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.