CVE-2026-21584

HIGHNVD 8.18.1—
EchelonGraph scoreMEDIUM confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-08-19. NVD baseline CVSS 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
Trending — 3 sources updated this week
8.1EG
EchelonGraph verdictPlan mitigationSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 8.1Exploit: None knownExposed services: Not assessed

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

This High severity Improper Authorization vulnerability was introduced in versions 10.0.0, 10.1.0, 10.2.0, 11.0.0, 12.0.0, and 12.1.0 of Bamboo Data Center. This Improper Authorization vulnerability, with a CVSS Score of 7.6, allows an authenticated attacker to gain unintended access and can lead to the exposure of resources or functionality, possibly providing attackers with sensitive information or even execute arbitrary code. Atlassian recommends that Bamboo Data Center customers upgrade to latest version, if you are unable to do so, upgrade your instance to one of the specified supported fixed versions: * Bamboo Data Center 10.2: Upgrade to a release greater than or equal to 10.2.22 * Bamboo Data Center 12.1: Upgrade to a release greater than or equal to 12.1.10 See the release notes (https://confluence.atlassian.com/bambooreleases/bamboo-release-notes-1189793869.html). You can download the latest version of Bamboo Data Center from the download center (https://www.atlassian.com/software/bamboo/download-archives). This vulnerability was reported via our Penetration Testing program.

CVSS v3
8.1
EG Score
8.1HIGHmedium confidence
EG Risk
37
EG Risk 37/100CISA 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
Severity81% × 45%
Exploitation0% × 40%
Automatability0% × 15%
CISA SSVC: Track at low or medium mission impact; Track* at high (mission-essential systems).
Action: No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix.
EPSS PROB
0.3%
EPSS %ILE
21st
KEV
Not listed

CISA SSVCTrack at low or medium mission impact; Track* at high (mission-essential systems).

No fix is confirmed yet. Restrict network exposure of the affected system or apply the vendor's mitigation within your standard update timelines, and watch the vendor's advisory for the fix.

Exploitation none (CISA Vulnrichment) · Automatable no (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

August 18, 2026

Last Modified

September 2, 2026

Advisory Details (2)

Auto-updated Aug 18, 2026
No patch confirmed yet.
generic

Loading...

https://jira.atlassian.com/browse/BAM-26468
generic

Security Bulletin - August 18 2026 | Atlassian Support | Atlassian Documentation

https://confluence.atlassian.com/pages/viewpage.action?pageId=1821999768

Vendor Advisories for CVE-2026-21584(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 22× in last 7d / 104× 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 186 total refreshes for this CVE.

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

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-21584?
CVE-2026-21584 is a high vulnerability published on August 18, 2026. This High severity Improper Authorization vulnerability was introduced in versions 10.0.0, 10.1.0, 10.2.0, 11.0.0, 12.0.0, and 12.1.0 of Bamboo Data Center. This Improper Authorization vulnerability, with a CVSS Score of 7.6, allows an authenticated attacker to gain unintended access and can lead…
When was CVE-2026-21584 disclosed?
CVE-2026-21584 was first published on August 18, 2026, with the most recent update on September 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21584 actively exploited?
CVE-2026-21584 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (21st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-21584?
CVE-2026-21584 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-21584?
No fix for CVE-2026-21584 is confirmed yet. Until one is published, restrict network exposure of the affected system or apply the vendor's mitigation — for example, keep it off the internet or limit it to trusted networks — and watch the vendor's advisory for the fix. The vendor advisories EchelonGraph has for CVE-2026-21584 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-21584

Explore →

Is Your Infrastructure Affected by CVE-2026-21584?

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

Book a Demo →Browse All CVEs