CVE-2024-21848Network attack vector

Continued call access via missing participant revocation

Published Apr 5, 2024 · Updated Feb 27, 2025

Improper access control in Mattermost Server 8.1.0 through 8.1.10 allows remote authenticated users to remain in an active channel call. The server does not revoke an existing call participant when that account is removed from the channel, leaving the live call session authorized. The account must already belong to the channel and join its active call; continued access exposes call audio after channel access is revoked.

CVSS severity3.1
Low
EPSS probability0.31%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper access control in Mattermost Server 8.1.0 through 8.1.10 allows remote authenticated users to remain in an active channel call. The server does not revoke an existing call participant when that account is removed from the channel, leaving the live call session authorized. The account must already belong to the channel and join its active call; continued access exposes call audio after channel access is revoked.

The record

CVE
CVE-2024-21848
Published
Apr 5, 2024
Updated
Feb 27, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-273, CWE-284, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Apr 5, 2024CVE publishedPublication date reported by the CVE source.
  2. Feb 27, 2025Record 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=8.1.0 <=8.1.10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=8.1.0 <=8.1.10

Published CVSS scores

3.1National Vulnerability DatabaseCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N
2.3GitHub Advisory DatabaseCVSS:4.0/AV:N/AC:H/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
3.1MattermostCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/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
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-273Improper Check for Dropped Privileges
CWE-284Improper Access Control
T1078Valid Accounts

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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