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TI-2017-14256 Aliases CVE-2017-20190GHSA-6399-j99h-665c

Some Microsoft technologies as used in Windows 8 through 11 allow a temporary client-side…

Priority LOW 30CWE-176Published · Updated

Key facts

Attack vector
—
Privileges required
—
User interaction
—
Attack complexity
—
Impact type
—
Confidentiality · integrity · availability
—
Fix status
No fix listed

No CVSS vector from any source. Fix status from CNA.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00262 18th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE names CISA-ADP · 1

CPEVersionsRoleVendor
cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*not specified by CISA-ADP—Microsoft
  • cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:* Versions not specified by CISA-ADP — ·Microsoft

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2017-20190
  2. 2026-10-03 Alias added: GHSA-6399-j99h-665c

References

Other 3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences