CVE-2026-55945 Microsoft CVE debrief

Who should care

Users of Microsoft Edge (Chromium-based) should be aware of this vulnerability and take necessary precautions to protect themselves. This includes applying the patch provided by Microsoft and ensuring that Microsoft Edge (Chromium-based) is up-to-date. Additionally, users should monitor for any suspicious activity.

Technical summary

The vulnerability is caused by a race condition in Microsoft Edge (Chromium-based) that allows an authorized attacker to disclose information locally. The vulnerability has a CVSS vector of CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:L/I:L/A:N. The vulnerability affects Microsoft Edge (Chromium-based) and has a CVSS score of 4.2 and a severity of MEDIUM.

Defensive priority

Medium priority

Recommended defensive actions

• Apply the patch provided by Microsoft
• Ensure that Microsoft Edge (Chromium-based) is up-to-date
• Monitor for any suspicious activity
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review

Evidence notes

The vulnerability was reported by an unknown source and was published on July 3, 2026. The CVE record was last modified on July 7, 2026. Evidence is limited, and defenders should verify the affected scope and vendor guidance. The vulnerability has a CVSS score of 4.2 and a severity of MEDIUM. Microsoft Edge (Chromium-based) is affected by this vulnerability. The CVE record provides additional details.

Sources and references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.