CVE-2026-21589

validatedZero produced an exploit or a check.

GHSA-gr66-x5pq-8g2g ↗EUVD-2026-92807 ↗

check availableZero validated a working check for it.not proven exploitableZero has a detection check, but hasn't produced a full working exploit yet.
cve.orgpublic pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).+13h11mkevAttacks confirmed in the real world.+2d
atlassian Bamboo Data Center All other versions; All versions
ETK-2026-703, permanent identifier
+21h16mTTV
35mAI analysisAnalysis: how long the AI spent reversing this signal.
Check if you are vulnerable
timeline
0 = trigger signal
trigger signal (cve.org) +0dpublic poc+0.5dcheck available+0.9dagent stoppedkev+2.0d
0
+1d

description

Affected Bamboo Data Center releases, along with listed Bitbucket, Confluence, Crowd, Jira, Crucible, and Fisheye releases, can expose files beneath the application web root. An unauthenticated remote attacker can retrieve a specific file if they already know its exact name and path. Directory listing is not available through this flaw.

mitigation

Upgrade Bamboo Data Center to 10.2.24 or 12.1.12, and upgrade other deployed affected products to their vendor-listed patched releases: Bitbucket 9.4.26, 10.2.8, or 10.5.1; Confluence 9.2.26 or 10.2.19; Jira 9.12.40, 10.3.26, or 11.3.12; and Crucible or Fisheye 4.9.15. Upgrade Crowd to 6.3.7, 7.0.3, or 7.2.4; confirm the appropriate 7.1.x target with the vendor because the supplied sources conflict.

check
available
exploit
no
automationDeterministic: a check that runs on its own, the same request on every target. Contextual: an agentic technique that needs to be applied per target, for bugs that depend on contextual flows.
deterministic
auth requiredWhether an attacker needs an account first, based on the CVSS vector's Privileges Required.
no
EPSSEstimate of the chance this CVE is exploited in the next 30 days. Refreshed daily.
13%96th percentile
agent run time
35m
cve.org record, t = 0The moment cve.org publishes the CVE in full.
2026-10-05 21:30Z
Δ to public pocExploit code has been published by someone. Source signals can also carry a PoC (Proof of Concept).
+13h11m
Δ to kevAttacks confirmed in the real world.
+2d

outcome

Check only, differential: the check fires on the vulnerable build and is silent on the patched one.

source signals

Public signals that triggered or updated the pipeline. These are inputs for the deltas above.

  1. 2026-10-05 21:30Z
    ghsa: trigger signal, started the run
  2. 2026-10-05 21:30Z
  3. 2026-10-06 06:58Z
    Critical Atlassian Flaw Lets Unauthenticated Attackers Read Known Files Across 8 Products
  4. 2026-10-06 18:09Z
  5. 2026-10-07 00:00Z
  6. 2026-10-07 11:49Z
    Atlassian Data Center Flaw Draws Exploitation Attempts Within Two Hours of Public Details
  7. 2026-10-15 00:00Z

this entry in the feed

GET /api/v1/feed/CVE-2026-21589

{
  "etk_id": "ETK-2026-703",
  "cve_id": "CVE-2026-21589",
  "display_id": "CVE-2026-21589",
  "ghsa_id": "GHSA-gr66-x5pq-8g2g",
  "euvd_id": "EUVD-2026-92807",
  "status": "published",
  "anchor_state": "anchored",
  "title": "Unauthenticated arbitrary file access in Bamboo Data Center",
  "summary": "Affected Bamboo Data Center releases, along with listed Bitbucket, Confluence, Crowd, Jira, Crucible, and Fisheye releases, can expose files beneath the application web root. An unauthenticated remote attacker can retrieve a specific file if they already know its exact name and path. Directory listing is not available through this flaw.",
  "mitigation": "Upgrade Bamboo Data Center to 10.2.24 or 12.1.12, and upgrade other deployed affected products to their vendor-listed patched releases: Bitbucket 9.4.26, 10.2.8, or 10.5.1; Confluence 9.2.26 or 10.2.19; Jira 9.12.40, 10.3.26, or 11.3.12; and Crucible or Fisheye 4.9.15. Upgrade Crowd to 6.3.7, 7.0.3, or 7.2.4; confirm the appropriate 7.1.x target with the vendor because the supplied sources conflict.",
  "vendor": "atlassian",
  "product": "Bamboo Data Center",
  "affected": [
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Bamboo Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Bamboo Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Bitbucket Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Bitbucket Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Confluence Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Confluence Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Crowd Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Crowd Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Crucible Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Crucible Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Fisheye Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Fisheye Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Jira Service Management Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Jira Service Management Server",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Jira Software Data Center",
      "purl": null
    },
    {
      "affected_notes": [
        "All other versions"
      ],
      "affected_ranges": [],
      "ecosystem": null,
      "fixed_versions": [],
      "package_name": "Jira Software Server",
      "purl": null
    }
  ],
  "cwes": null,
  "cvss_score": 9.3,
  "cvss_src": "cna_vendor",
  "cvss_vector": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
  "epss_score": 0.1271,
  "epss_percentile": 0.9624,
  "epss_asof": "2026-10-20",
  "automation": "deterministic",
  "check": true,
  "check_confidence_basis": "differential",
  "exploit": false,
  "pipeline_minutes": 35.172016883333335,
  "t0_at": "2026-10-05T21:30:00.390000+00:00",
  "signals": {
    "check": {
      "at": "2026-10-06T18:46:07.423920+00:00",
      "days": 0.8861925222222222,
      "is_lower_bound": false,
      "measured_at": "2026-10-05T21:30:00.390000+00:00",
      "url": null
    },
    "kev": {
      "at": "2026-10-07T00:00:00+00:00",
      "days": 2,
      "is_lower_bound": false,
      "measured_at": "2026-10-05T21:30:00.390000+00:00",
      "precision": "day",
      "url": "https://vulncheck.com/cve/CVE-2026-21589"
    },
    "public_poc": {
      "at": "2026-10-06T10:40:59+00:00",
      "days": 0.5492894675925926,
      "is_lower_bound": false,
      "measured_at": "2026-10-05T21:30:00.390000+00:00",
      "url": "https://github.com/watchtowrlabs/watchTowr-vs-Atlassian-CVE-2026-21589"
    },
    "trigger_signal": {
      "at": "2026-10-05T21:30:00.390000+00:00",
      "days": 0,
      "is_lower_bound": false,
      "measured_at": "2026-10-05T21:30:00.390000+00:00",
      "url": "https://github.com/advisories/GHSA-gr66-x5pq-8g2g"
    }
  }
}

published 2026-10-06 01:01Z
last change 2026-10-21 10:52Z

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