CVE-2021-27085 Microsoft Internet Explorer: command or code injection
In plain words: The program treats text it receives as instructions instead of plain data. The attacker can run commands on the machine — often the whole device is taken over.
Confirmed exploited by CISA on · US federal patch deadline Nov 17, 2021
What to do
- Install Microsoft's security update for Internet Explorer. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Let the browser auto-update and relaunch it when it asks — the fix is not active until you do.
- Keep extensions to a minimum and remove ones you do not recognise.
- Stop using Internet Explorer and any browser that no longer gets updates.
Who is affected
Could reach you. This one is aimed at devices or apps of the kind people own.
What's at risk: A malicious or hacked website can be enough. Browser bugs are often the first step in a longer attack on the whole computer or phone.
The details
- Official name
- Microsoft Internet Explorer Remote Code Execution Vulnerability
- Product
- Microsoft Internet Explorer
- CISA description
- Microsoft Internet Explorer contains an unspecified vulnerability that allows for remote code execution.
- Type of flaw
- Command or code injection
- Confirmed exploited
- Nov 3, 2021
- US federal patch deadline
- Nov 17, 2021
Ask Cleus about it
Ask about a vulnerability, an update, a weird message, or the news. Plain-word answers, free, no account.
Answering about CVE-2021-27085 ·
Questions about CVE-2021-27085
Is CVE-2021-27085 being exploited?
Yes. CISA added CVE-2021-27085 to its Known Exploited Vulnerabilities catalog on Nov 3, 2021, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2021-27085?
Install Microsoft's security update for Internet Explorer. If no update exists, follow the vendor's workaround or stop using the product until one ships. Let the browser auto-update and relaunch it when it asks — the fix is not active until you do.
Am I affected by CVE-2021-27085?
Only if you use Microsoft Internet Explorer. This one is aimed at devices or apps of the kind people own.