CVE-2017-20190

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.

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Weakness Type (CWE)

CWE-176 CWE-176

References

Other 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

Frequently Asked Questions

What is 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. NOTE: third parties dispute whether the computational cost of interpreting Unicode data should be considered a vulnerability.

How do I check if I'm vulnerable to CVE-2017-20190? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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