CVE-2023-6459Network attack vector

Channel ID disclosure via metrics grouping labels

Published Dec 6, 2023 · Updated Dec 16, 2024

Information disclosure in Mattermost 7.8.13 and earlier and 8.1.4 and earlier allows remote attackers to read channel IDs via metrics. The Calls plugin groups calls by an identifier and emits that identifier as a metrics label, even though the value is the underlying channel ID. Exposure requires the Calls metrics HTTP endpoint to be reachable and a corresponding call metric to be present; the reported consequence is channel-ID disclosure only.

CVSS severity5.3
Medium
EPSS probability0.53%
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 7.8.13 and earlier and 8.1.4 and earlier allows remote attackers to read channel IDs via metrics. The Calls plugin groups calls by an identifier and emits that identifier as a metrics label, even though the value is the underlying channel ID. Exposure requires the Calls metrics HTTP endpoint to be reachable and a corresponding call metric to be present; the reported consequence is channel-ID disclosure only.

The record

CVE
CVE-2023-6459
Published
Dec 6, 2023
Updated
Dec 16, 2024
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-200
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Dec 6, 2023CVE publishedPublication date reported by the CVE source.
  2. Dec 16, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=0 <=7.8.13
  2. Affected versionversion=0 <=8.1.4

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Mattermost · Mattermostversion=0 <=7.8.13; version=0 <=8.1.4

Published CVSS scores

5.3Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

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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-200Exposure of Sensitive Information to an Unauthorized Actor

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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