Denial of Service Vulnerability in memono Notepad by memono
CVE-2021-47944

8.7HIGH

Key Information:

Vendor

Memono

Status
Notepad
Vendor
CVE Published:
10 May 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2021-47944?

memono Notepad version 4.2 is susceptible to a denial of service vulnerability that can be exploited by attackers to crash the application. By pasting excessively long character buffers—around 350,000 repeated characters—into the note fields, attackers can cause the application to become unstable and crash on iOS devices. This vulnerability highlights the importance of input validation and application reliability in mobile environments.

Affected Version(s)

Notepad 4.2

Exploit Proof of Concept (PoC)

PoC code is written by security researchers to demonstrate the vulnerability can be exploited. PoC code is also a key component for weaponization which could lead to ransomware.

CVE-2021-47944 - Proof of Concept

References

https://www.exploit-db.com/exploits/49977
exploit
https://www.vulncheck.com/advisories/memono-notepad-denia...
third-party-advisory

CVSS V4

Score:
8.7
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Attack Required:
None
Privileges Required:
Undefined
User Interaction:
None

Timeline

  • 🟡

    Public PoC available

  • đź‘ľ

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Geovanni Ruiz
.