What’s Vulnerable › Vulnerabilities

CVE-2017-20190

• Severity: unknown
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.3% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2024-03-27 · updated 2026-06-17
• Weakness: CWE-176

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.

Affected products

• Microsoft Corporation Windows: from 8 through 11

References

• https://aka.ms/windowsbugbar
• https://en.wikipedia.org/wiki/Zalgo_text
• https://talk.dynalist.io/t/dynalist-is-vulnerable-to-zalgo/1234
• https://aka.ms/windowsbugbar
• https://en.wikipedia.org/wiki/Zalgo_text
• https://talk.dynalist.io/t/dynalist-is-vulnerable-to-zalgo/1234

Get alerted when CVE-2017-20190 or the next vulnerability affects your stack