CVE-2021-23124

HIGHNVD 6.18.8
EchelonGraph scoreHIGH confidence

Score elevated to 8.8 because EPSS predicts 81% probability of exploitation within the next 30 days (top 0.4% of all CVEs). NVD baseline CVSS 6.1 retained for reference. Confidence: see factors.

Triggered by: EPSS exploit prediction ≥85%
Sources: epss, nvd
Elevated
8.8EG
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 81%
CISA-KEV: Not listedEPSS PROB: 81%CVSS: 6.1Exploit: Elevated riskExposed: 0

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

An issue was discovered in Joomla! 3.9.0 through 3.9.23. The lack of escaping in mod_breadcrumbs aria-label attribute allows XSS attacks.

CVSS v3
6.1
EG Score
8.8(high)
EG Risk
77(Track)
EG Risk 77/100SSVC: 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
Severity88% × 45%
Exploitation81% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
81%
EPSS %ILE
100%
KEV
Not listed

Published

January 12, 2021

Last Modified

November 21, 2024

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 5× in last 7d / 20× 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. 2026-08-20 10:31 UTCOSV refresh
  2. 2026-08-19 17:01 UTCEPSS rescore
  3. 2026-08-18 13:45 UTCEPSS rescore
  4. 2026-08-16 02:11 UTCEPSS rescore
  5. 2026-08-15 01:27 UTCEPSS rescore
  6. 2026-08-12 13:47 UTCEPSS rescore
  7. 2026-08-09 13:43 UTCEPSS rescore
  8. 2026-08-08 16:33 UTCEPSS rescore
  9. 2026-08-07 16:23 UTCEPSS rescore
  10. 2026-08-05 06:10 UTCOSV refresh
  11. 2026-08-04 15:06 UTCEPSS rescore
  12. 2026-08-02 02:24 UTCEPSS rescore
  13. 2026-07-30 16:25 UTCEPSS rescore
  14. 2026-07-30 01:27 UTCEPSS rescore
  15. 2026-07-30 01:27 UTCEPSS rescore
  16. 2026-07-26 14:52 UTCEPSS rescore
  17. 2026-07-25 14:15 UTCEPSS rescore
  18. 2026-07-24 14:15 UTCEPSS rescore
  19. 2026-07-23 01:57 UTCEG score recompute 2.70
  20. 2026-07-22 22:44 UTCEG score recompute
  21. 2026-07-22 14:05 UTCEPSS rescore
  22. 2026-07-20 17:04 UTCEPSS rescore
  23. 2026-07-19 04:22 UTCOSV refresh
  24. 2026-07-16 17:00 UTCEPSS rescore
  25. 2026-07-15 16:55 UTCEPSS rescore
Show 67 more
  1. 2026-07-15 16:55 UTCEPSS rescore
  2. 2026-07-13 22:27 UTCEPSS rescore
  3. 2026-07-13 22:27 UTCEPSS rescore
  4. 2026-07-11 08:25 UTCEPSS rescore
  5. 2026-07-09 19:07 UTCEPSS rescore
  6. 2026-07-04 06:29 UTCEPSS rescore
  7. 2026-07-04 06:29 UTCEPSS rescore
  8. 2026-07-02 16:57 UTCEPSS rescore
  9. 2026-07-01 10:48 UTCOSV refresh
  10. 2026-06-30 23:20 UTCEPSS rescore
  11. 2026-06-30 23:20 UTCEPSS rescore
  12. 2026-06-28 14:05 UTCEPSS rescore
  13. 2026-06-28 04:54 UTCEPSS rescore
  14. 2026-06-28 04:54 UTCEPSS rescore
  15. 2026-06-25 13:48 UTCEPSS rescore
  16. 2026-06-25 13:48 UTCEPSS rescore
  17. 2026-06-23 21:31 UTCEPSS rescore
  18. 2026-06-23 21:31 UTCEPSS rescore
  19. 2026-06-21 14:54 UTCEPSS rescore
  20. 2026-06-21 14:54 UTCEPSS rescore
  21. 2026-06-21 01:58 UTCEPSS rescore
  22. 2026-06-21 01:57 UTCEPSS rescore
  23. 2026-06-19 19:24 UTCEPSS rescore
  24. 2026-06-19 19:24 UTCEPSS rescore
  25. 2026-06-16 17:50 UTCEPSS rescore
  26. 2026-06-15 17:46 UTCEPSS rescore
  27. 2026-06-14 23:15 UTCEPSS rescore
  28. 2026-06-13 22:58 UTCEPSS rescore
  29. 2026-06-13 16:43 UTCOSV refresh
  30. 2026-06-12 23:10 UTCEPSS rescore
  31. 2026-06-12 23:10 UTCEPSS rescore
  32. 2026-06-11 13:58 UTCEPSS rescore
  33. 2026-06-10 22:16 UTCEPSS rescore
  34. 2026-06-10 22:16 UTCEPSS rescore
  35. 2026-06-10 13:20 UTCEPSS rescore
  36. 2026-06-08 14:15 UTCEPSS rescore
  37. 2026-06-08 14:15 UTCEPSS rescore
  38. 2026-06-07 15:23 UTCEPSS rescore
  39. 2026-06-07 15:23 UTCEPSS rescore
  40. 2026-06-06 13:46 UTCEPSS rescore
  41. 2026-06-06 13:46 UTCEPSS rescore
  42. 2026-06-06 13:46 UTCEPSS rescore
  43. 2026-06-05 22:45 UTCEPSS rescore
  44. 2026-06-05 22:45 UTCEPSS rescore
  45. 2026-06-05 06:09 UTCEPSS rescore
  46. 2026-06-05 06:09 UTCEPSS rescore
  47. 2026-06-05 06:08 UTCEPSS rescore
  48. 2026-06-04 13:10 UTCEPSS rescore
  49. 2026-06-02 20:11 UTCEPSS rescore
  50. 2026-06-02 20:11 UTCEPSS rescore
  51. 2026-06-01 13:50 UTCEPSS rescore
  52. 2026-06-01 13:50 UTCEPSS rescore
  53. 2026-05-31 22:29 UTCEPSS rescore
  54. 2026-05-31 22:29 UTCEPSS rescore
  55. 2026-05-31 00:15 UTCEPSS rescore
  56. 2026-05-31 00:15 UTCEPSS rescore
  57. 2026-05-29 13:42 UTCEPSS rescore
  58. 2026-05-28 13:43 UTCEPSS rescore
  59. 2026-05-28 13:43 UTCEPSS rescore
  60. 2026-05-27 13:39 UTCEPSS rescore
  61. 2026-05-26 22:14 UTCEG score recompute
  62. 2026-05-26 22:14 UTCGHSA enrichment
  63. 2026-05-26 13:42 UTCEPSS rescore
  64. 2026-05-26 13:42 UTCEPSS rescore
  65. 2026-05-26 07:17 UTCEPSS rescore
  66. 2026-05-26 07:17 UTCEPSS rescore
  67. 2026-05-24 16:49 UTCEPSS rescore

Frequently asked(5)

What is CVE-2021-23124?
CVE-2021-23124 is a high vulnerability published on January 12, 2021. An issue was discovered in Joomla! 3.9.0 through 3.9.23. The lack of escaping in mod_breadcrumbs aria-label attribute allows XSS attacks.
When was CVE-2021-23124 disclosed?
CVE-2021-23124 was first published in the National Vulnerability Database on January 12, 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-2021-23124 actively exploited?
CVE-2021-23124 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 81% probability of exploitation in the next 30 days, which ranks it in the top 0.4% of all scored CVEs.
What is the CVSS score of CVE-2021-23124?
CVE-2021-23124 has a CVSS v3 base score of 6.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 8.8.
How do I remediate CVE-2021-23124?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2021-23124, 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

Explore the affected products and dependency analysis for CVE-2021-23124

Explore →

Is Your Infrastructure Affected by CVE-2021-23124?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.