CVE-2021-26084: Atlassian Confluence Server and Data Center Object-Graph Navigation Language (OGNL) Injection Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation as urgent.
Atlassian Confluence Server and Data Server contain an Object-Graph Navigation Language (OGNL) injection vulnerability that may allow an unauthenticated attacker to execute code.
CSIRTS triage
- What
- An Object-Graph Navigation Language (OGNL) injection vulnerability may allow unauthenticated code execution.
- Who is affected
- Users of Atlassian Confluence Server and Data Center are affected by this vulnerability.
- Urgency
- Immediate remediation is necessary due to active exploitation and critical severity.
- Action
- Upgrade to the latest version of Confluence Server and Data Center.
AI-assisted analysis generated from the source advisory — verify against the original.
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Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2021-26084
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2021-26084Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 99.9% of all EPSS-scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2021-26084 | coverage & exploitation status | NVD · CVE.org |
Same CVEs, other sources
How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.
- unknownexploitedA method to assess 'forgivable' vs 'unforgivable' vulnerabilitiesncsc-uk
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