CVE-2021-25943

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2021-05-17. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Elevated
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 3.3%CVSS: 9.8Exploit: Elevated riskExposed services: Not assessed

A fixed version is listed under Patch Availability — apply it.

Prototype pollution vulnerability in '101' versions 1.0.0 through 1.6.3 allows an attacker to cause a denial of service and may lead to remote code execution.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
75
EG Risk 75/100CISA SSVC

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
Severity98% × 45%
Exploitation40% × 40%
Automatability100% × 15%
CISA SSVC: Track at low, Track* at medium and Attend at high mission impact.
Action: A fixed version is listed under Patch Availability. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
3.3%
EPSS %ILE
88th
KEV
Not listed

CISA SSVCTrack at low, Track* at medium and Attend at high mission impact.

A fixed version is listed under Patch Availability. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Mission impact is CISA's Mission & Well-being decision point, and only you can judge it: high means the affected system is essential to your organisation's mission, or its compromise could cause irreversible harm to people. CISA's decision table

Published

May 14, 2021

Last Modified

April 30, 2025

Advisory Details (2)

Auto-updated Oct 10, 2026
Fixed version listed under Patch Availability.
generic

CVE-2021-25943 | Mend Vulnerability Database

https://www.whitesourcesoftware.com/vulnerability-database/CVE-2021-25943
generic

101/set.js at d87f63ce2a4cbdc476e8287abd78327c3144d646 · tjmehta/101 · GitHub

https://github.com/tjmehta/101/blob/d87f63ce2a4cbdc476e8287abd78327c3144d646/set.js#L52

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
npm101—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFix by version rangeDependents
101—
  • 1.0.0 through 1.6.3: no fix on record
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 6× in last 7d / 33× 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 184 total refreshes for this CVE.

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

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Frequently asked(5)

What is CVE-2021-25943?
CVE-2021-25943 is a critical vulnerability published on May 14, 2021. Prototype pollution vulnerability in '101' versions 1.0.0 through 1.6.3 allows an attacker to cause a denial of service and may lead to remote code execution.
When was CVE-2021-25943 disclosed?
CVE-2021-25943 was first published on May 14, 2021, with the most recent update on April 30, 2025. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-25943 actively exploited?
CVE-2021-25943 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3.3% probability of exploitation in the next 30 days (88th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2021-25943?
CVE-2021-25943 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2021-25943?
A fixed version for CVE-2021-25943 is listed under Patch Availability on this page: update to the version listed for your package.

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