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MosquittoApplication · Eclipse

CVE-2024-3935

MEDIUM · 6.5 CVSS v3.1 Published 2024-10-30
Fix available
A fix is available. Upgrade to 2.0.19 or later.
See remediation →
71/100
Remediation priority · Elevated
Public exploit Remotely reachable Zero-click Patch available

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
In Eclipse Mosquito, versions from 2.0.0 through 2.0.18, if a Mosquitto broker is configured to create an outgoing bridge connection, and that bridge connection has an incoming topic configured that makes use of topic remapping, then if the remote connection sends a crafted PUBLISH packet to the broker a double free will occur with a subsequent crash of the broker.

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
How this class of weakness works · CWE-415

The same block of memory is freed twice, corrupting the allocator's bookkeeping in ways an attacker can shape toward code execution. It usually stems from tangled ownership of a pointer. The fix is clear, single ownership of each allocation and clearing pointers once they are freed.

General guidance for the double free class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

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
MosquittoApplication
Affected:>= 2.0.0, < 2.0.19

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
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

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 2.0.19 or later
Fixed in 2.0.19
Vendor patch github.com →
Recommended fix High confidence

Mosquitto 2.0.19

  1. Check current Mosquitto version using: mosquitto -version
  2. Backup the current Mosquitto configuration files (typically in /etc/mosquitto/ or /etc/mosquitto.d/)
  3. Stop the Mosquitto broker service: sudo systemctl stop mosquitto (or appropriate service command for your system)
  4. Upgrade Mosquitto to version 2.0.19 or later using your system's package manager or by compiling from source
  5. Verify the new version is installed: mosquitto -version
  6. Restart the Mosquitto broker service: sudo systemctl start mosquitto
  7. Test that the broker functions correctly and bridge connections work as expected

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

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

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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-2024-3935 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
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