CVE-2021-3156 Sudo Sudo: memory-safety flaw
In plain words: The program mishandles the memory it uses to keep track of data. A specially made input can scramble that memory. Usually lets an attacker crash the program or run their own code with its permissions.
Confirmed exploited by CISA on · US federal patch deadline Apr 27, 2022
What to do
- Install Sudo's security update for Sudo. 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
- Sudo Heap-Based Buffer Overflow Vulnerability
- Product
- Sudo Sudo
- CISA description
- Sudo contains an off-by-one error that can result in a heap-based buffer overflow, which allows for privilege escalation.
- Type of flaw
- Memory-safety flaw (CWE-122, CWE-193)
- Confirmed exploited
- Apr 6, 2022
- US federal patch deadline
- Apr 27, 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-2021-3156 ·
Questions about CVE-2021-3156
Is CVE-2021-3156 being exploited?
Yes. CISA added CVE-2021-3156 to its Known Exploited Vulnerabilities catalog on Apr 6, 2022, which means there is reliable evidence of real-world attacks.
How do I fix CVE-2021-3156?
Install Sudo's security update for Sudo. 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-2021-3156?
Only if you use Sudo Sudo. Aimed mostly at company systems — you are affected through the companies you use, not your own phone.