CVE-2021-41303

CRITICALNVD 9.89.8
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 76.7%, top 1% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Trending — 3 sources updated this weekElevated
9.8
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 77%
CISA-KEV: Not listedEPSS: 77%CVSS: 9.8Exploit: NoneExposed: 0

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

Apache Shiro before 1.8.0, when using Apache Shiro with Spring Boot, a specially crafted HTTP request may cause an authentication bypass. Users should update to Apache Shiro 1.8.0.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
79(Track*)
EG Risk 79/100SSVC: Track*

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%
Exploitation77% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS
99.5%
KEV
Not listed

Published

September 17, 2021

Last Modified

November 21, 2024

Affected Packages

(1 across 1 ecosystem)
Maven(1)
PackageVulnerable rangeFixed inDependents
org.apache.shiro:shiro-core1.0.0-incubating ... 1.7.1 (23 versions)1.8.0

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 36× 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.

  1. 2026-07-23 02:04 UTCEG score recompute
  2. 2026-07-22 22:50 UTCEG score recompute
  3. 2026-07-22 14:06 UTCEPSS rescore
  4. 2026-07-21 15:22 UTCEPSS rescore
  5. 2026-07-21 15:22 UTCEPSS rescore
  6. 2026-07-20 17:05 UTCEPSS rescore
  7. 2026-07-19 14:29 UTCEPSS rescore
  8. 2026-07-18 11:29 UTCOSV refresh
  9. 2026-07-15 16:55 UTCEPSS rescore
  10. 2026-07-15 16:55 UTCEPSS rescore
  11. 2026-07-15 01:58 UTCEPSS rescore
  12. 2026-07-13 22:27 UTCEPSS rescore
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  14. 2026-07-12 05:44 UTCEPSS rescore
  15. 2026-07-11 08:25 UTCEPSS rescore
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  17. 2026-07-09 19:07 UTCEPSS rescore
  18. 2026-07-08 15:12 UTCEPSS rescore
  19. 2026-07-06 16:25 UTCEPSS rescore
  20. 2026-07-06 16:25 UTCEPSS rescore
  21. 2026-07-06 02:21 UTCEPSS rescore
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  23. 2026-07-05 02:28 UTCEPSS rescore
  24. 2026-07-05 02:28 UTCEPSS rescore
  25. 2026-07-02 16:57 UTCEPSS rescore
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  1. 2026-07-01 15:04 UTCEPSS rescore
  2. 2026-06-30 23:20 UTCEPSS rescore
  3. 2026-06-30 23:20 UTCEPSS rescore
  4. 2026-06-30 13:30 UTCOSV refresh
  5. 2026-06-29 14:04 UTCEPSS rescore
  6. 2026-06-28 04:54 UTCEPSS rescore
  7. 2026-06-28 04:54 UTCEPSS rescore
  8. 2026-06-25 13:48 UTCEPSS rescore
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  10. 2026-06-23 21:31 UTCEPSS rescore
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  12. 2026-06-21 14:55 UTCEPSS rescore
  13. 2026-06-21 01:58 UTCEPSS rescore
  14. 2026-06-21 01:58 UTCEPSS rescore
  15. 2026-06-17 17:51 UTCEPSS rescore
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  17. 2026-06-17 17:51 UTCEPSS rescore
  18. 2026-06-15 17:46 UTCEPSS rescore
  19. 2026-06-14 23:15 UTCEPSS rescore
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  21. 2026-06-13 22:58 UTCEPSS rescore
  22. 2026-06-13 22:58 UTCEPSS rescore
  23. 2026-06-12 23:10 UTCEPSS rescore
  24. 2026-06-12 21:10 UTCOSV refresh
  25. 2026-06-11 13:58 UTCEPSS rescore
  26. 2026-06-11 13:58 UTCEPSS rescore
  27. 2026-06-10 22:16 UTCEPSS rescore
  28. 2026-06-10 22:16 UTCEPSS rescore
  29. 2026-06-10 13:20 UTCEPSS rescore
  30. 2026-06-07 15:23 UTCEPSS rescore
  31. 2026-06-07 15:23 UTCEPSS rescore
  32. 2026-06-06 13:46 UTCEPSS rescore
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  34. 2026-06-05 22:45 UTCEPSS rescore
  35. 2026-06-05 06:09 UTCEPSS rescore
  36. 2026-06-05 06:09 UTCEPSS rescore
  37. 2026-06-04 13:10 UTCEPSS rescore
  38. 2026-06-04 13:10 UTCEPSS rescore
  39. 2026-06-02 20:11 UTCEPSS rescore
  40. 2026-06-02 20:11 UTCEPSS rescore
  41. 2026-06-01 13:50 UTCEPSS rescore
  42. 2026-06-01 13:50 UTCEPSS rescore
  43. 2026-05-29 13:42 UTCEPSS rescore
  44. 2026-05-28 13:43 UTCEPSS rescore
  45. 2026-05-28 13:43 UTCEPSS rescore
  46. 2026-05-27 13:39 UTCEPSS rescore
  47. 2026-05-27 13:39 UTCEPSS rescore
  48. 2026-05-26 10:14 UTCEG score recompute
  49. 2026-05-26 07:17 UTCEPSS rescore
  50. 2026-05-26 07:17 UTCEPSS rescore
  51. 2026-05-26 07:17 UTCEPSS rescore

Frequently asked(5)

What is CVE-2021-41303?
CVE-2021-41303 is a critical vulnerability published on September 17, 2021. Apache Shiro before 1.8.0, when using Apache Shiro with Spring Boot, a specially crafted HTTP request may cause an authentication bypass. Users should update to Apache Shiro 1.8.0.
When was CVE-2021-41303 disclosed?
CVE-2021-41303 was first published in the National Vulnerability Database on September 17, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2021-41303 actively exploited?
CVE-2021-41303 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.5% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2021-41303?
CVE-2021-41303 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2021-41303?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-41303, 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.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2021-41303

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