CVE-2021-47970 Macaron Notes 5.5 Denial of Service via Buffer Overflow
Attackers can crash Macaron Notes by pasting excessively long strings into note fields, causing a denial of service.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2021-47970?
CVE-2021-47970 is a high-severity denial of service vulnerability in Macaron Notes, published on 16 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Macaron Notes 5.5 contains a denial of service vulnerability that allows attackers to crash the application by creating notes with excessively long character strings. Attackers can generate a payload containing 350000 repeated characters and paste it into a note field to trigger application crash and stop functionality.
Weakness: CWE-789
Which versions are affected by CVE-2021-47970?
How do I fix CVE-2021-47970?
No fix has been published for CVE-2021-47970 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2021-47970 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2021-47970 exists.
Sources
Also known as GHSA-4439-4hh6-5j2w.