CVE-2016-11066Network attack vector

Personal data disclosure via unsanitized initial_load response

Published Jun 19, 2020 · Updated Aug 6, 2024

Information disclosure in Mattermost Server before 3.1.1 allows remote attackers to obtain personal data through the initial_load API. The getInitialLoad handler returned the full client license and feedback email without removing license-holder contact details from non-administrator responses. Requests require no prior authentication; exposure is limited to license-holder contact and license metadata, without data modification or service interruption.

CVSS severity8.7
High
EPSS probability1.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information disclosure in Mattermost Server before 3.1.1 allows remote attackers to obtain personal data through the initial_load API. The getInitialLoad handler returned the full client license and feedback email without removing license-holder contact details from non-administrator responses. Requests require no prior authentication; exposure is limited to license-holder contact and license metadata, without data modification or service interruption.

The record

CVE
CVE-2016-11066
Published
Jun 19, 2020
Updated
Aug 6, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-359, CWE-200, T1213
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jun 19, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.7GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0NIST NVDAV:N/AC:L/Au:N/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-359Exposure of Private Personal Information to an Unauthorized Actor
CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1213Data from Information Repositories

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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