CVE-2026-78850 Matomo CVE debrief

Who should care

Defenders responsible for Matomo installations, particularly those using v.5.11.2, should assess exposure and verify the vulnerability. This includes operators, platform administrators, vulnerability management teams, and security teams who need to prioritize verifying the vulnerability and assessing exposure in their environments. The affected product or component is Matomo v.5.11.2, and the vulnerability-management impact involves verifying and remediate

Why it matters

CVE-2026-78850 is a vulnerability in Matomo v.5.11.2 that allows remote attackers to obtain sensitive information. Defenders should prioritize verifying the vulnerability and assessing exposure in their environments.

• Verify vulnerability in Matomo v.5.11.2
• Assess exposure in environments
• Monitor for exploitation attempts

Technical summary

The vulnerability is in the SiteContentDetector / SitesManager component of Matomo v.5.11.2, allowing remote attackers to obtain sensitive information. This issue is related to inadequate access controls or input validation, which could lead to unauthorized disclosure of sensitive data. Defenders should prioritize verifying the vulnerability in Matomo v.5.11.2 and assessing exposure in their environments. The technical impact includes potential data breaches and unauthorized access to sensitive information. The source-grounded technical framing indicates that the vulnerability is confirmed in Matomo v.5.11.2, but further details are limited.

Defensive priority

Defenders should prioritize verifying the vulnerability in Matomo v.5.11.2 and assessing exposure in their environments.

Recommended defensive actions

• Verify the vulnerability in Matomo v.5.11.2
• Assess exposure in environments using Matomo v.5.11.2
• Monitor for potential exploitation attempts
• Review compensating controls for exposed systems while remediation is scheduled and verified
• Check relevant monitoring, detection, and logs for exposed assets that need extra review
• Track exceptions, retest remediated assets, and close the item only after evidence is documented
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up

Evidence notes

The vulnerability is described in the CVE record and the source item from cve_program_cvelist_v5. However, the details are limited, and further verification is required to understand the scope of the vulnerability.

Sources and references

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.