CVE-2021-40647 Memory corruption in n/a
A heap-based buffer overflow in man2html allows attackers to cause a denial of service or potentially execute arbitrary code via a crafted file.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2021-40647?
CVE-2021-40647 is a medium-severity memory corruption vulnerability in n/a, published on 9 Sep 2022. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
In man2html 1.6g, a specific string being read in from a file will overwrite the size parameter in the top chunk of the heap. This at least causes the program to segmentation abort if the heap size parameter isn't aligned correctly. In version before GLIBC version 2.29 and aligned correctly, it allows arbitrary write anywhere in the programs memory.
Weakness: CWE-787
Which versions are affected by CVE-2021-40647?
It affects 1 product.
Products include Man2html Project Man2html.
How do I fix CVE-2021-40647?
Apply the vendor's patch.
Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.
Is CVE-2021-40647 being exploited?
There is no known exploitation of CVE-2021-40647 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as DEBIAN-CVE-2021-40647, GHSA-p3mv-74p6-4mgc, MGASA-2025-0097, UBUNTU-CVE-2021-40647.