Exploitation evidence
Known exploited · CISA KEV listed
Added 2021-11-03. Ransomware campaign use: Known.
CISA required action: Apply updates per vendor instructions.
CISA due date: 2021-11-17. This is the catalog’s deadline, not an assessment of your organization’s exposure.
KEV checked 13 Nov 2026, 00:20 Jerusalem · Original catalog ↗Reported products and versions
Atlassian / Confluence Server
Default status: Not specified
- affected: unspecified to < 6.13.23 (custom)
- affected: 6.14.0 to < unspecified (custom)
- affected: unspecified to < 7.4.11 (custom)
- affected: 7.5.0 to < unspecified (custom)
- affected: unspecified to < 7.11.6 (custom)
- affected: 7.12.0 to < unspecified (custom)
- affected: unspecified to < 7.12.5 (custom)
Atlassian / Confluence Data Center
Default status: Not specified
- affected: unspecified to < 6.13.23 (custom)
- affected: 6.14.0 to < unspecified (custom)
- affected: unspecified to < 7.4.11 (custom)
- affected: 7.5.0 to < unspecified (custom)
- affected: unspecified to < 7.11.6 (custom)
- affected: 7.12.0 to < unspecified (custom)
- affected: unspecified to < 7.12.5 (custom)
Fixes and workarounds
No explicit solution text in the downloaded CVE record. Consult the vendor advisory; unaffected version ranges are shown above as reported, not inferred as a patch recommendation.
Sources and related reporting
Observed change timeline
History begins when Egret first downloads each source. It is not the complete upstream CVE history.
12 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-12",
"epss": 0.99999,
"percentile": 0.99993
}10 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-10",
"epss": 0.99999,
"percentile": 0.99993
}09 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-09",
"epss": 0.99999,
"percentile": 0.99993
}08 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-08",
"epss": 0.99999,
"percentile": 0.99993
}07 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-07",
"epss": 0.99999,
"percentile": 0.99993
}06 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-06",
"epss": 0.99999,
"percentile": 0.99993
}06 Nov 2026, 06:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-05",
"epss": 0.99999,
"percentile": 0.99993
}06 Nov 2026, 00:20 Jerusalem · CVE Program record changed
Stored CNA snapshot at this observation.
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"assignerShortName": "atlassian",
"cveId": "CVE-2021-26084",
"datePublished": "2021-08-30T06:30:14.248Z",
"dateReserved": "2021-01-25T00:00:00.000Z",
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}04 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-04",
"epss": 0.99999,
"percentile": 0.99993
}03 Nov 2026, 18:20 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-03",
"epss": 0.99999,
"percentile": 0.99993
}03 Nov 2026, 02:22 Jerusalem · EPSS observation updated
Stored EPSS snapshot at this observation.
{
"date": "2026-11-02",
"epss": 0.99999,
"percentile": 0.99993
}03 Nov 2026, 02:22 Jerusalem · CISA KEV status changed
Stored KEV snapshot at this observation.
{
"cveID": "CVE-2021-26084",
"cwes": [
"CWE-917"
],
"dateAdded": "2021-11-03",
"dueDate": "2021-11-17",
"forensicTriage": "No",
"knownRansomwareCampaignUse": "Known",
"notes": "https://nvd.nist.gov/vuln/detail/CVE-2021-26084",
"product": "Confluence Server and Data Center",
"requiredAction": "Apply updates per vendor instructions.",
"shortDescription": "Atlassian Confluence Server and Data Server contain an Object-Graph Navigation Language (OGNL) injection vulnerability that may allow an unauthenticated attacker to execute code.",
"vendorProject": "Atlassian",
"vulnerabilityName": "Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection Vulnerability"
}