CVE-2025-20630Network attack vector

Authenticated mobile crash via non-string attachment fields

Published Jan 16, 2025 · Updated Jan 16, 2025

Improper input validation in Mattermost Mobile 2.22.0 and earlier allows remote authenticated users to crash the app via a crafted post. The attachment-field handler casts post attachment field values to strings without validating their types, and an incompatible value causes an unhandled failure. Channel posting access is required; rendering the crafted post interrupts the affected mobile client but does not crash the Mattermost server.

CVSS severity6.5
Medium
EPSS probability0.61%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper input validation in Mattermost Mobile 2.22.0 and earlier allows remote authenticated users to crash the app via a crafted post. The attachment-field handler casts post attachment field values to strings without validating their types, and an incompatible value causes an unhandled failure. Channel posting access is required; rendering the crafted post interrupts the affected mobile client but does not crash the Mattermost server.

The record

CVE
CVE-2025-20630
Published
Jan 16, 2025
Updated
Jan 16, 2025
Vendor
Mattermost
Product
Mattermost
Classifications
CWE-1287, T1499
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 16, 2025CVE publishedPublication date reported by the CVE source.
  2. Jan 16, 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=0 <=<=2.22.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Mattermost · Mattermostversion=0 <=<=2.22.0

Published CVSS scores

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
6.5Mattermost, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

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-1287Improper Validation of Specified Type of Input
T1499Endpoint Denial of Service

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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