CVE-2026-21571

HIGHNVD 8.88.8—
EchelonGraph scoreMEDIUM confidence

Score 8.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-04-21. NVD baseline CVSS 8.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
8.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1%CVSS: 8.8Exploit: None knownExposed: 0

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

This Critical severity OS Command Injection vulnerability was introduced in versions 9.6.0, 10.0.0, 10.1.0, 10.2.0, 11.0.0, 11.1.0, 12.0.0, and 12.1.0 of Bamboo Data Center.   This RCE (Remote Code Execution) vulnerability, with a CVSS Score of 9.4 and a CVSS Vector of CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H allows an authenticated attacker to execute commands on the remote system, which has high impact to confidentiality, high impact to integrity, high impact to availability, and requires no user interaction.   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 9.6.0: Upgrade to a release greater than or equal to 9.6.25 Bamboo Data Center 10.2: Upgrade to a release greater than or equal to 10.2.18  Bamboo Data Center 12.1: Upgrade to a release greater than or equal to 12.1.6 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]).

CVSS v3
8.8
EG Score
8.8(medium)
EG Risk
40(Track)
EG Risk 40/100SSVC: 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%
Exploitation1% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
1%
EPSS %ILE
70%
KEV
Not listed

Published

April 21, 2026

Last Modified

August 10, 2026

Advisory Details (2)

Auto-updated Jul 31, 2026
No patch confirmed yet.
generic

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https://jira.atlassian.com/browse/BAM-26364
generic

Security Bulletin - April 21 2026 | Atlassian Support | Atlassian Documentation

https://confluence.atlassian.com/pages/viewpage.action?pageId=1770913890

Vendor Advisories for CVE-2026-21571(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 5× in last 7d / 25× 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 251 total refreshes for this CVE.

  1. 2026-09-13 16:47 UTCEPSS rescore
  2. 2026-09-12 15:01 UTCEPSS rescore
  3. 2026-09-11 14:52 UTCEPSS rescore
  4. 2026-09-10 09:34 UTCEPSS rescore
  5. 2026-09-08 22:00 UTCEPSS rescore
  6. 2026-09-07 16:01 UTCEPSS rescore
  7. 2026-09-06 13:47 UTCEPSS rescore
  8. 2026-09-06 13:47 UTCEPSS rescore
  9. 2026-09-04 05:06 UTCEPSS rescore
  10. 2026-09-02 14:11 UTCEPSS rescore
  11. 2026-09-01 13:53 UTCEPSS rescore
  12. 2026-09-01 04:39 UTCEPSS rescore
  13. 2026-08-30 19:17 UTCEPSS rescore
  14. 2026-08-30 01:22 UTCEPSS rescore
  15. 2026-08-28 21:41 UTCEPSS rescore
  16. 2026-08-27 14:25 UTCEPSS rescore
  17. 2026-08-26 14:46 UTCEPSS rescore
  18. 2026-08-25 13:48 UTCEPSS rescore
  19. 2026-08-23 00:19 UTCEPSS rescore
  20. 2026-08-21 23:49 UTCEPSS rescore
  21. 2026-08-20 22:55 UTCEPSS rescore
  22. 2026-08-19 17:03 UTCEPSS rescore
  23. 2026-08-18 13:48 UTCEPSS rescore
  24. 2026-08-17 13:47 UTCEPSS rescore
  25. 2026-08-16 14:56 UTCEPSS rescore
Show 75 more
  1. 2026-08-16 06:18 UTCEG score recompute
  2. 2026-08-16 06:18 UTCGHSA enrichment
  3. 2026-08-16 02:14 UTCEPSS rescore
  4. 2026-08-15 01:30 UTCEPSS rescore
  5. 2026-08-14 15:51 UTCGHSA enrichment
  6. 2026-08-14 04:29 UTCEG score recompute
  7. 2026-08-14 04:29 UTCGHSA enrichment
  8. 2026-08-13 22:00 UTCEPSS rescore
  9. 2026-08-13 08:45 UTCGHSA enrichment
  10. 2026-08-12 18:40 UTCEG score recompute
  11. 2026-08-12 18:40 UTCGHSA enrichment
  12. 2026-08-12 13:50 UTCEPSS rescore
  13. 2026-08-11 19:43 UTCEG score recompute
  14. 2026-08-11 19:43 UTCGHSA enrichment
  15. 2026-08-11 13:42 UTCEPSS rescore
  16. 2026-08-11 08:14 UTCEG score recompute
  17. 2026-08-11 08:14 UTCGHSA enrichment
  18. 2026-08-11 00:00 UTCEPSS rescore
  19. 2026-08-10 20:50 UTCEG score recompute▼ 0.60
  20. 2026-08-10 20:50 UTCGHSA enrichment
  21. 2026-08-10 20:49 UTCNVD updateCVSS v3 → 8.8 · severity → HIGH
  22. 2026-08-10 12:49 UTCGHSA enrichment
  23. 2026-08-10 08:27 UTCGHSA enrichment
  24. 2026-08-10 04:30 UTCGHSA enrichment
  25. 2026-08-10 00:34 UTCGHSA enrichment
  26. 2026-08-09 20:37 UTCGHSA enrichment
  27. 2026-08-09 16:40 UTCEG score recompute
  28. 2026-08-09 16:40 UTCGHSA enrichment
  29. 2026-08-09 13:46 UTCEPSS rescore
  30. 2026-08-09 12:43 UTCGHSA enrichment
  31. 2026-08-09 07:39 UTCGHSA enrichment
  32. 2026-08-09 03:42 UTCEG score recompute
  33. 2026-08-09 03:42 UTCGHSA enrichment
  34. 2026-08-08 16:37 UTCEPSS rescore
  35. 2026-08-08 08:43 UTCGHSA enrichment
  36. 2026-08-08 04:46 UTCGHSA enrichment
  37. 2026-08-08 00:48 UTCGHSA enrichment
  38. 2026-08-07 20:51 UTCGHSA enrichment
  39. 2026-08-07 16:54 UTCEG score recompute
  40. 2026-08-07 16:54 UTCGHSA enrichment
  41. 2026-08-07 12:57 UTCGHSA enrichment
  42. 2026-08-06 21:23 UTCGHSA enrichment
  43. 2026-08-06 17:26 UTCEG score recompute
  44. 2026-08-06 17:26 UTCGHSA enrichment
  45. 2026-08-06 13:46 UTCEPSS rescore
  46. 2026-08-06 11:57 UTCGHSA enrichment
  47. 2026-08-06 07:05 UTCGHSA enrichment
  48. 2026-08-06 03:08 UTCGHSA enrichment
  49. 2026-08-05 23:11 UTCEG score recompute
  50. 2026-08-05 23:11 UTCGHSA enrichment
  51. 2026-08-05 19:17 UTCEPSS rescore
  52. 2026-08-04 15:10 UTCEPSS rescore
  53. 2026-08-04 10:38 UTCEPSS rescore
  54. 2026-08-04 05:34 UTCGHSA enrichment
  55. 2026-08-04 01:20 UTCGHSA enrichment
  56. 2026-08-03 21:23 UTCEG score recompute
  57. 2026-08-03 21:23 UTCGHSA enrichment
  58. 2026-08-03 10:35 UTCEPSS rescore
  59. 2026-08-03 00:43 UTCGHSA enrichment
  60. 2026-08-02 20:43 UTCGHSA enrichment
  61. 2026-08-02 16:46 UTCGHSA enrichment
  62. 2026-08-02 12:49 UTCEG score recompute
  63. 2026-08-02 12:49 UTCGHSA enrichment
  64. 2026-08-02 02:26 UTCEPSS rescore
  65. 2026-08-01 04:15 UTCEPSS rescore
  66. 2026-07-30 01:30 UTCEPSS rescore
  67. 2026-07-27 14:13 UTCEPSS rescore
  68. 2026-07-26 14:54 UTCEPSS rescore
  69. 2026-07-26 14:54 UTCEPSS rescore
  70. 2026-07-25 14:17 UTCEPSS rescore
  71. 2026-07-25 14:17 UTCEPSS rescore
  72. 2026-07-24 14:17 UTCEPSS rescore
  73. 2026-07-23 14:18 UTCEPSS rescore
  74. 2026-07-23 14:18 UTCEPSS rescore
  75. 2026-07-23 03:06 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-21571?
CVE-2026-21571 is a high vulnerability published on April 21, 2026. This Critical severity OS Command Injection vulnerability was introduced in versions 9.6.0, 10.0.0, 10.1.0, 10.2.0, 11.0.0, 11.1.0, 12.0.0, and 12.1.0 of Bamboo Data Center. This RCE (Remote Code Execution) vulnerability, with a CVSS Score of 9.4 and a CVSS Vector of…
When was CVE-2026-21571 disclosed?
CVE-2026-21571 was first published in the National Vulnerability Database on April 21, 2026, with the most recent update on August 10, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-21571 actively exploited?
CVE-2026-21571 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1% probability of exploitation in the next 30 days, which ranks it in the top 30.2% of all scored CVEs.
What is the CVSS score of CVE-2026-21571?
CVE-2026-21571 has a CVSS v3 base score of 8.8 (NVD).
How do I remediate CVE-2026-21571?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-21571, 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

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