CVE-2021-47971

My Notes Safe 5.3 contains a denial of service vulnerability that allows attackers to crash the application by pasting excessively long character strings into note fields. Attackers can generate a payload containing 350000 repeated characters and paste it twice into a new note to trigger an application crash.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.exploit-db.com/exploits/49954
https://www.vulncheck.com/advisories/my-notes-safe-denial-of-service-via-buffer-overflow

Configurations

No configuration.

History

16 May 2026, 16:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-16 16:16

Updated : 2026-05-18 17:32

NVD link : CVE-2021-47971

Mitre link : CVE-2021-47971

CVE.ORG link : CVE-2021-47971

JSON object : View

Products Affected

No product.

CWE

CWE-789

Memory Allocation with Excessive Size Value

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