Denial of Service Vulnerability in My Notes Safe by My Notes Safe
CVE-2021-47971

8.7HIGH

Key Information:

Vendor

My-notes-safe

Status
My Notes Safe
Vendor
CVE Published:
16 May 2026

Badges

👾 Exploit Exists🟡 Public PoC

What is CVE-2021-47971?

My Notes Safe version 5.3 is susceptible to a denial of service vulnerability that arises when excessively long character strings are pasted into note fields. Attackers can exploit this flaw by generating a payload consisting of 350,000 repeated characters and pasting it into a new note field twice, leading to a crash of the application. This vulnerability underscores the importance of input validation and can have significant implications for users and their data.

Affected Version(s)

My Notes Safe 5.3

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-2021-47971 - Proof of Concept

References

https://www.exploit-db.com/exploits/49954
exploit
https://www.vulncheck.com/advisories/my-notes-safe-denial...
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

  • 👾

    Exploit known to exist

  • Vulnerability published

  • Vulnerability Reserved

Credit

Geovanni Ruiz
.