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PatchSiren cyber security CVE debrief

CVE-2019-3396 Atlassian CVE debrief

CVE-2019-3396 is an Atlassian Confluence Server and Data Center server-side template injection vulnerability that CISA lists in its Known Exploited Vulnerabilities catalog. Because CISA marks it as known exploited and notes known ransomware campaign use, defenders should treat exposed Confluence instances as a priority patching and verification target.

Vendor
Atlassian
Product
Confluence Server and Data Server
CVSS
Unknown
CISA KEV
Listed
Original CVE published
2021-11-03
Original CVE updated
2021-11-03
Advisory published
2021-11-03
Advisory updated
2021-11-03

Who should care

Atlassian Confluence Server and Data Center administrators, vulnerability management teams, incident responders, and anyone responsible for internet-facing collaboration platforms or change control.

Technical summary

The supplied corpus identifies the issue as a server-side template injection affecting Atlassian Confluence Server and Data Center. CISA’s KEV entry confirms active exploitation and indicates known ransomware campaign use. The corpus does not provide version ranges, exploit mechanics, or remediation steps beyond applying vendor updates per instructions.

Defensive priority

High. Known exploited in the wild, with ransomware campaign use noted by CISA, so affected Confluence deployments should be patched and validated urgently.

Recommended defensive actions

  • Identify all Atlassian Confluence Server and Data Center instances, including internet-facing and internally reachable deployments.
  • Apply updates per vendor instructions as directed in the CISA KEV record.
  • Verify patch status after remediation and confirm vulnerable instances are no longer present.
  • Review Confluence access logs and administrative activity for signs of unauthorized use around the exposure window.
  • If patching is delayed, reduce exposure by restricting access to trusted networks and monitoring closely until remediation is complete.

Evidence notes

Source evidence is limited to the CISA KEV JSON entry and official CVE/NVD references. The corpus establishes the product, vulnerability class, KEV status, required action, and known ransomware campaign use, but does not include affected versions, exploit details, or a vendor advisory excerpt.

Sources and references

Verified primary and authoritative sources

  • CVE-2019-3396 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2019-3396

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2019-3396 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2019-3396

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

  • CISA Known Exploited Vulnerabilities catalog

    Publisher, destination, and source semantics verified

    URL: https://www.cisa.gov/known-exploited-vulnerabilities-catalog

    Cybersecurity and Infrastructure Security Agency - Official CISA catalog of vulnerabilities known to be exploited in the wild.

Supplemental references

  • Source item URL

    Unverified legacy reference

    URL: https://www.cisa.gov/sites/default/files/feeds/known_exploited_vulnerabilities.json

    cisa_kev

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.