Mattermost ServerApplication · Mattermost

CVE-2023-3591

HIGH · 8.2 CVSS v3.1 Published 2023-07-17
Fix available
A fix is available. Upgrade to 7.8.7 / 7.9.5 or later.
See remediation →
91/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Mattermost fails to invalidate previously generated password reset tokens when a new reset token was created.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

In Mattermost, when a user requests a new password reset token, any previously generated tokens for that user remain valid. An attacker with access to an old token (via email interception, log exposure, or other means) can still use it to reset the user's password even after a newer token was requested.

MitigationApply the vendor patch to ensure previously generated password reset tokens are invalidated when a new reset token is created. Until patched, monitor for unauthorized password reset attempts.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Mattermost ServerApplication
Affected:>= 7.8.0, < 7.8.7>= 7.9.0, < 7.9.5>= 7.10.0, < 7.10.3

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
Low
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Mattermost Server version
    Run 'mmctl version' or check the Mattermost System Console > About page to find the exact version number installed
    Affected if Installed version falls within 7.8.0-7.8.6, 7.9.0-7.9.4, or 7.10.0-7.10.2
  2. Review password reset token logs
    Search Mattermost logs for 'password reset' or 'token' events using grep or the search functionality in the admin console
    Affected if Multiple password reset tokens exist for the same user or old tokens appear in logs
  3. Audit recent password reset activity
    Check the Mattermost audit logs for password reset events, looking for multiple reset requests per user account
    Affected if A user shows more than one password reset token generation without corresponding successful password changes
  4. Inspect password reset token storage
    Query the database (Tokens table) to see if multiple active reset tokens exist for individual users
    Affected if More than one active password reset token is stored for any user account

You are affected if your Mattermost Server version is 7.8.0-7.8.6, 7.9.0-7.9.4, or 7.10.0-7.10.2 AND you have any users who have requested password resets multiple times.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 7.8.7 / 7.9.5 / 7.10.3 or later
Fixed in 7.8.77.9.57.10.3
Interim mitigation

Apply the vendor patch to ensure previously generated password reset tokens are invalidated when a new reset token is created. Until patched, monitor for unauthorized password reset attempts.

Recommended fix High confidence

Mattermost Server 7.10.3 (or later stable release)

  1. Back up the Mattermost database and configuration files before proceeding with the upgrade
  2. Stop the Mattermost server service
  3. Upgrade Mattermost Server to version 7.8.7, 7.9.5, or 7.10.3 (or later)
  4. Verify the upgrade was successful by checking the server version
  5. Start the Mattermost server service
  6. Verify that password reset functionality works correctly and that old tokens are now invalidated when new ones are requested
Caveat Review Mattermost release notes for any breaking changes between your current version and the target upgrade version

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Mattermost Server Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing3.0 h
  • Review / QA2.0 h
11.0 hours of engineering $1,930
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $3,088.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-3591 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-3591 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data