CVE-2021-47944

HIGHNVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-05-10. NVD baseline CVSS 7.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: Elevated riskExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

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.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
65(Attend)
EG Risk 65/100SSVC: Attend

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
21%
KEV
Not listed

Published

May 10, 2026

Last Modified

July 25, 2026

Advisory Details (2)

Auto-updated May 10, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic

memono Notepad 4.2 Denial of Service via Buffer Overflow | Advisories | VulnCheck

https://www.vulncheck.com/advisories/memono-notepad-denial-of-service-via-buffer-overflow
generic🟡 PoC Available

memono Notepad Version 4.2 - Denial of Service (PoC) - iOS local Exploit

https://www.exploit-db.com/exploits/49977

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 5× in last 7d / 29× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 249 total refreshes for this CVE.

  1. 2026-09-15 03:06 UTCEPSS rescore
  2. 2026-09-12 14:57 UTCEPSS rescore
  3. 2026-09-11 14:49 UTCEPSS rescore
  4. 2026-09-11 09:33 UTCEPSS rescore
  5. 2026-09-08 21:57 UTCEPSS rescore
  6. 2026-09-07 15:58 UTCEPSS rescore
  7. 2026-09-06 13:45 UTCEPSS rescore
  8. 2026-09-05 15:25 UTCEPSS rescore
  9. 2026-09-04 13:57 UTCEPSS rescore
  10. 2026-09-04 05:03 UTCEPSS rescore
  11. 2026-09-02 14:09 UTCEPSS rescore
  12. 2026-09-01 13:51 UTCEPSS rescore
  13. 2026-08-30 19:14 UTCEPSS rescore
  14. 2026-08-30 01:19 UTCEPSS rescore
  15. 2026-08-28 21:38 UTCEPSS rescore
  16. 2026-08-27 14:22 UTCEPSS rescore
  17. 2026-08-26 14:43 UTCEPSS rescore
  18. 2026-08-25 13:46 UTCEPSS rescore
  19. 2026-08-24 14:13 UTCEPSS rescore
  20. 2026-08-23 18:46 UTCEG score recompute
  21. 2026-08-23 18:46 UTCGHSA enrichment
  22. 2026-08-21 23:46 UTCEPSS rescore
  23. 2026-08-20 22:52 UTCEPSS rescore
  24. 2026-08-19 17:01 UTCEPSS rescore
  25. 2026-08-18 13:45 UTCEPSS rescore
Show 75 more
  1. 2026-08-17 13:44 UTCEPSS rescore
  2. 2026-08-17 11:20 UTCEG score recompute
  3. 2026-08-17 11:20 UTCGHSA enrichment
  4. 2026-08-16 14:53 UTCEPSS rescore
  5. 2026-08-16 04:29 UTCEG score recompute
  6. 2026-08-16 04:29 UTCGHSA enrichment
  7. 2026-08-16 02:11 UTCEPSS rescore
  8. 2026-08-15 01:27 UTCEPSS rescore
  9. 2026-08-14 15:10 UTCGHSA enrichment
  10. 2026-08-14 03:03 UTCEG score recompute
  11. 2026-08-14 03:03 UTCGHSA enrichment
  12. 2026-08-13 21:57 UTCEPSS rescore
  13. 2026-08-13 04:45 UTCGHSA enrichment
  14. 2026-08-12 16:39 UTCEG score recompute
  15. 2026-08-12 16:39 UTCGHSA enrichment
  16. 2026-08-12 13:48 UTCEPSS rescore
  17. 2026-08-11 15:48 UTCEG score recompute
  18. 2026-08-11 15:48 UTCGHSA enrichment
  19. 2026-08-11 13:38 UTCEPSS rescore
  20. 2026-08-11 01:13 UTCEG score recompute
  21. 2026-08-11 01:13 UTCGHSA enrichment
  22. 2026-08-10 02:31 UTCGHSA enrichment
  23. 2026-08-09 14:24 UTCEG score recompute
  24. 2026-08-09 14:24 UTCGHSA enrichment
  25. 2026-08-09 13:44 UTCEPSS rescore
  26. 2026-08-09 02:18 UTCEG score recompute
  27. 2026-08-09 02:18 UTCGHSA enrichment
  28. 2026-08-08 16:34 UTCEPSS rescore
  29. 2026-08-08 01:53 UTCEG score recompute
  30. 2026-08-08 01:53 UTCGHSA enrichment
  31. 2026-08-07 16:24 UTCEPSS rescore
  32. 2026-08-07 13:47 UTCGHSA enrichment
  33. 2026-08-07 01:40 UTCEG score recompute
  34. 2026-08-07 01:40 UTCGHSA enrichment
  35. 2026-08-06 13:44 UTCEPSS rescore
  36. 2026-08-06 10:07 UTCGHSA enrichment
  37. 2026-08-05 22:01 UTCEG score recompute
  38. 2026-08-05 22:01 UTCGHSA enrichment
  39. 2026-08-05 19:15 UTCEPSS rescore
  40. 2026-08-04 15:06 UTCEPSS rescore
  41. 2026-08-04 10:34 UTCEPSS rescore
  42. 2026-08-03 19:27 UTCGHSA enrichment
  43. 2026-08-03 02:40 UTCGHSA enrichment
  44. 2026-08-02 14:33 UTCGHSA enrichment
  45. 2026-08-02 02:26 UTCEG score recompute
  46. 2026-08-02 02:26 UTCGHSA enrichment
  47. 2026-08-02 02:24 UTCEPSS rescore
  48. 2026-08-01 04:13 UTCEPSS rescore
  49. 2026-07-30 16:25 UTCEPSS rescore
  50. 2026-07-30 01:28 UTCEPSS rescore
  51. 2026-07-28 15:33 UTCEPSS rescore
  52. 2026-07-26 14:52 UTCEPSS rescore
  53. 2026-07-26 08:24 UTCEG score recompute
  54. 2026-07-26 08:24 UTCGHSA enrichment
  55. 2026-07-25 14:15 UTCEPSS rescore
  56. 2026-07-24 14:15 UTCEPSS rescore
  57. 2026-07-24 14:15 UTCEPSS rescore
  58. 2026-07-23 14:16 UTCEPSS rescore
  59. 2026-07-23 02:06 UTCEG score recompute
  60. 2026-07-22 22:53 UTCEG score recompute
  61. 2026-07-22 14:06 UTCEPSS rescore
  62. 2026-07-20 17:05 UTCEPSS rescore
  63. 2026-07-19 14:29 UTCEPSS rescore
  64. 2026-07-19 02:27 UTCEPSS rescore
  65. 2026-07-19 02:27 UTCEPSS rescore
  66. 2026-07-18 10:02 UTCEPSS rescore
  67. 2026-07-16 17:00 UTCEPSS rescore
  68. 2026-07-16 17:00 UTCEPSS rescore
  69. 2026-07-15 16:55 UTCEPSS rescore
  70. 2026-07-15 01:58 UTCEPSS rescore
  71. 2026-07-15 01:58 UTCEPSS rescore
  72. 2026-07-13 22:27 UTCEPSS rescore
  73. 2026-07-13 06:11 UTCEPSS rescore
  74. 2026-07-13 06:11 UTCEPSS rescore
  75. 2026-07-12 05:44 UTCEPSS rescore

Frequently asked(5)

What is CVE-2021-47944?
CVE-2021-47944 is a high vulnerability published on May 10, 2026. 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…
When was CVE-2021-47944 disclosed?
CVE-2021-47944 was first published in the National Vulnerability Database on May 10, 2026, with the most recent update on July 25, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-47944 actively exploited?
CVE-2021-47944 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 79.1% of all scored CVEs.
What is the CVSS score of CVE-2021-47944?
CVE-2021-47944 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2021-47944?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-47944, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

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