15 September 2026
1. What is being reported?
Hackers have found and are using a previously unknown security weakness (called a zero-day) that affects both Google Chrome and Microsoft Windows. They use this flaw to install a malicious program named GRIMWEDGE on targeted computers.
2. What this means in plain English
If your organisation uses Windows computers and Google Chrome, attackers could potentially break into your systems without your knowledge, leading to data theft or disruption. Small organisations without strong security measures may be more vulnerable.
3. Could this affect a small business?
Any small business, charity, or club using Windows and Chrome could be affected, especially if updates are not regularly applied. Those using other browsers or operating systems are less likely to be impacted, but should still remain cautious.
4. What to do now
- Ensure Windows and Google Chrome are updated to the latest versions immediately.
- If automatic updates are not enabled, turn them on to receive security patches promptly.
- Avoid clicking on suspicious links or opening unexpected email attachments.
- Ask your IT provider to check if your systems are protected against this specific threat.
5. Ask your IT provider
Can you confirm that our Windows and Google Chrome software have been updated to protect against the latest zero-day vulnerability exploited by hackers deploying GRIMWEDGE?
6. Bottom line
Keep your Windows and Chrome software up to date to reduce the risk from this active hacking threat.
Information based on reputable security reporting and CISA KEV.