⚠️ The Threat
Google has released emergency security patches for two newly discovered vulnerabilities in Chrome:
- CVE‑2025‑6554
- CVE‑2025‑6558
Both are zero-day vulnerabilities being actively exploited in the wild, marking the fourth Chrome zero-day wave in 2025.
🛑 These vulnerabilities also affect all Chromium-based browsers:
Microsoft Edge, Brave, Opera, Vivaldi, and others.
📌 Vulnerability Summary
| CVE ID | CVE‑2025‑6554 / 6558 |
|---|
| Type | Zero-Day (Use-After-Free / Memory Corruption) |
| Affected Browsers | Chrome, Edge, Brave, Opera (Chromium-based) |
| Status | Actively Exploited in the Wild |
| Severity | High to Critical |
| Patch Available | Yes (Chrome version 125.0.6423.121+) |
🧠 Technical Details (What We Know)
While Google has limited public disclosure (to avoid further exploitation), initial research indicates:
- CVE‑2025‑6554:
A use-after-free vulnerability in the WebAssembly module. Attackers exploit it to execute arbitrary code remotely via crafted web content. - CVE‑2025‑6558:
Likely a memory corruption flaw triggered during cross-site rendering or tab isolation failures, potentially allowing sandbox escape.
🎯 Real-World Exploitation
Threat actors are reportedly:
- Hosting malicious websites that exploit the flaws once visited
- Delivering drive-by payloads in phishing emails
- Embedding exploits in malvertising campaigns
⚠️ No user interaction beyond visiting a compromised website may be required.
🛡️ CyberDudeBivash Recommendations
✔️ What to Do Immediately:
- Patch Your Browser:
- Update Chrome to v125.0.6423.121 or newer
- Ensure updates for Microsoft Edge, Brave, Opera, and Vivaldi
- Enforce Browser Auto-Update Policies:
- Push updates organization-wide via GPO or MDM
- Enable Enhanced Safe Browsing (ESB) in Chrome:
- Helps detect malicious websites in real-time
- Monitor for IOCs:
- Track outbound connections from browsers to unknown IPs
- Use EDR to scan browser cache/memory for anomalies
- Limit Browser Plugin Usage:
- Remove unnecessary extensions that could increase attack surface
🧬 AI-Sec Insight by CyberDudeBivash
“Browser-based zero-days are now the easiest entry points into enterprises. With the help of AI, adversaries are building polymorphic drive-by payloads that adapt on the fly. Browser hygiene and endpoint visibility are non-negotiable.”