CVE-2021-47944
CVE-2021-47944 is a high-severity vulnerability with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-789.
Key facts
- Severity: High (CVSS 3.x base score 7.5)
- CVSS v4: 8.7
- EPSS exploit prediction: 0% (21st percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2021-34804
- Weakness: CWE-789
- Published:
- Last modified:
Description
memono Notepad 4.2 contains a denial of service vulnerability that allows attackers to crash the application by pasting excessively long character buffers 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 on iOS devices.
Frequently asked questions
- What is CVE-2021-47944?
- memono Notepad 4.2 contains a denial of service vulnerability that allows attackers to crash the application by pasting excessively long character buffers 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 on iOS devices.
- How severe is CVE-2021-47944?
- CVE-2021-47944 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2021-47944 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (21st percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2021-47944?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2021-47944 have an EU (EUVD) identifier?
- Yes. CVE-2021-47944 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2021-34804.
- When was CVE-2021-47944 published?
- CVE-2021-47944 was published on 2026-05-10 and last updated on 2026-07-25.
References
- https://www.exploit-db.com/exploits/49977
- https://www.vulncheck.com/advisories/memono-notepad-denial-of-service-via-buffer-overflow
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