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VULNERABILITY BRIEF🟢 Low Vulnerability

Security Bypass in Microsoft Edge (CVE-2026-45492) Allows Restricted Function Access via Origin Validation Flaw

A cross‑device sign‑in flaw in Microsoft Edge (CVE‑2026‑45492) lets remote attackers reach restricted browser functionality after a victim visits a malicious page. The vulnerability scores 4.3 (Low) on CVSS and has been patched by Microsoft, but unpatched endpoints remain a supply‑chain risk for enterprises.

LiveThreat™ Intelligence · 📅 June 05, 2026· 📰 zerodayinitiative.com
🟢
Severity
Low
VU
Type
Vulnerability
🎯
Confidence
High
🏢
Affected
2 sector(s)
Actions
5 recommended
📰
Source
zerodayinitiative.com

Security Bypass in Microsoft Edge (CVE‑2026‑45492) Allows Restricted Function Access via Origin Validation Flaw

What It Is — A cross‑device sign‑in flaw in Microsoft Edge fails to properly validate the origin of web content, enabling a remote attacker to reach restricted browser functionality. The issue is classified as a security‑bypass rather than a full code‑execution bug.

Exploitability — Exploitation requires user interaction (the victim must visit a malicious page or open a crafted file). No public exploit code has been released, and the CVSS v3.1 base score is 4.3 (Low). Microsoft has already issued a patch.

Affected Products — Microsoft Edge (all supported versions at the time of disclosure).

TPRM Impact

  • Edge is bundled with Windows and widely deployed across enterprise desktops, making any unpatched endpoint a potential weak link in a supply‑chain risk profile.
  • The flaw can be chained with other vulnerabilities to elevate privileges or exfiltrate data from corporate web applications that rely on Edge’s managed sign‑in.

Recommended Actions

  • Deploy Microsoft’s security update for CVE‑2026‑45492 immediately across all managed endpoints.
  • Enforce strict web‑content filtering to block untrusted domains that could host the malicious page.
  • Disable or restrict the cross‑device managed sign‑in feature where not required.
  • Monitor Edge telemetry for anomalous origin‑validation failures or unexpected navigation events.
  • Update third‑party risk registers to note Microsoft Edge as a critical component requiring timely patching.

Source: Zero Day Initiative Advisory ZDI‑26‑329

📰 Original Source
http://www.zerodayinitiative.com/advisories/ZDI-26-329/

This LiveThreat Intelligence Brief is an independent analysis. Read the original reporting at the link above.

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