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My Notes Safe CVE-2021-47971

| EUVDEUVD-2021-34828 HIGH
Memory Allocation with Excessive Size Value (CWE-789)
2026-05-16 VulnCheck GHSA-w4w9-25xj-f9j4
8.7
CVSS 4.0 · NVD
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Vulnerability Assessment

Weakness
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Memory allocation limits
Impact

CVSS score of 8.7 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. EPSS exploitation probability: 0.04%.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the high-severity affected system.

This Week Schedule remediation this week. Why: HIGH severity (CVSS 7.0-8.9).
No patch listed yet 0.0% exploitation probability (EPSS)

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AnalysisAI

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. Rated high severity (CVSS 8.7), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available and no vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affected VersionsENISA

My Notes Safe 5.3

Affected Packages

euvd my_notes_safe no fix

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

Checking this CVE against your own stacks and servers is part of the Basic plan and up.

Technical ContextAI · show details

This vulnerability is classified under CWE-789. 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. Affected products include: My-Notes-Safe My Notes Safe.

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  • Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 8.7 HIGH
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Attack Requirements
None
Privileges Required
None
User Interaction
None
Vulnerable system: Confidentiality
None
Vulnerable system: Integrity
None
Vulnerable system: Availability
High
Subsequent system: Confidentiality
None
Subsequent system: Integrity
None
Subsequent system: Availability
None

Lifecycle Timeline

2
CVSS changed
May 16, 2026 - 16:22 NVD
7.5 (HIGH) 8.7 (HIGH)
CVE Published
May 16, 2026 - 15:26 cve.org
HIGH 8.7

DescriptionCVE.org

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.

Threat Intelligence Overview

EPSS Score
0.0%
Top 88% exploitable
Exploit
POC
Public exploit code exists
Data Quality
6 sources
Confidence: High
EUVD NVD CVE.org EPSS Vulnrichment Exploit-DB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity HIGH
CISA KEV No
Public POC Yes
EPSS 0.0%
Patch available No
Active threat No
Deciding rule
HIGH severity (CVSS 7.0-8.9)
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation
Poc
System Exposure· derived
Open
Automatable
Yes
Human Impact· derived
Medium
Technical Impact
Partial

Priority Score

64
Low Medium High Critical
KEV: 0
EPSS: 0
CVSS: +44
PoC: +20
Weaponized: 0
Threat intel: 0
Gov advisory: 0

Attack Technique

Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.

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