CVE-2021-35247 SolarWinds Serv-U: software flaw
In plain words: A mistake in the software that attackers have found a way to abuse. Depends on the product — see the description and the vendor advisory.
Confirmed exploited by CISA on · US federal patch deadline Feb 4, 2022
What to do
- Install SolarWinds's security update for Serv-U. If no update exists, follow the vendor's workaround or stop using the product until one ships.
- Keep a list of every internet-facing server you run so nothing is forgotten.
- Patch anything in this catalog first, ahead of normal patch cycles.
- Put admin and file-transfer apps behind a VPN or single sign-on instead of the open internet.
Who is affected
Work IT. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.
What's at risk: Mass data theft and ransomware: a single flaw in a file-transfer or email server has exposed thousands of organisations at once.
The details
- Official name
- SolarWinds Serv-U Improper Input Validation Vulnerability
- Product
- SolarWinds Serv-U
- CISA description
- SolarWinds Serv-U versions 15.2.5 and earlier contain an improper input validation vulnerability that allows attackers to build and send queries without sanitization.
- Type of flaw
- Software flaw (CWE-20)
- Confirmed exploited
- Jan 21, 2022
- US federal patch deadline
- Feb 4, 2022
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-2021-35247 ·
Questions about CVE-2021-35247
Is CVE-2021-35247 being exploited?
Yes. CISA added CVE-2021-35247 to its Known Exploited Vulnerabilities catalog on Jan 21, 2022, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2021-35247?
Install SolarWinds's security update for Serv-U. If no update exists, follow the vendor's workaround or stop using the product until one ships. Keep a list of every internet-facing server you run so nothing is forgotten.
Am I affected by CVE-2021-35247?
Only if you use SolarWinds Serv-U. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.