Security readout for executives and security teams
Plain-English summary
CVE-2018-19417 is a memory-safety flaw in the Contiki-NG MQTT server before version 4.2. A specially crafted MQTT PUBLISH message could overflow a fixed stack buffer. The reported impact is remote code execution because the MQTT server shares memory with other OS and server modules.
Executive priority
Prioritize this for any internet-facing or untrusted-network Contiki-NG MQTT deployment. The issue has potential remote code execution impact, but available evidence does not show active exploitation or broad affected-product mapping.
Technical view
parse_publish_vhdr() copies MQTT PUBLISH variable-header input into a fixed-size topic buffer without checking length. The buffer fits MQTT_MAX_TOPIC_LENGTH bytes, default 64. The source describes possible stack smashing by overwriting the return address, with broad memory access due to Contiki-NG architecture.
Likely exposure
Exposure is limited to deployments running the Contiki-NG MQTT server before 4.2, especially where that MQTT service is reachable by untrusted clients. The source bundle does not identify packaged downstream products or CPEs.
Exploitation context
The source describes a plausible remote code execution condition, but the bundle provides no CVSS score, no CWE entry, and no evidence of active exploitation. It is not listed as KEV in the supplied data.
Researcher notes
The key evidence is the missing length check before memcpy into a fixed-size topic buffer in parse_publish_vhdr(). Validate against the exact Contiki-NG branch because the CVE record’s structured affected-product fields are incomplete.
Mitigation direction
- Identify Contiki-NG deployments running the MQTT server before 4.2.
- Upgrade to Contiki-NG 4.2 or later where project guidance confirms applicability.
- Restrict MQTT server access to trusted networks and clients.
- Disable the MQTT server where it is not operationally required.
- Check the Contiki-NG issue and vendor guidance for build-specific fixes.
Validation and detection
- Inventory firmware and source versions for Contiki-NG usage.
- Confirm whether the MQTT server component is compiled and enabled.
- Review network exposure for MQTT listener reachability.
- Check code for parse_publish_vhdr() length validation in deployed branches.
- Document compensating controls if upgrade is not immediately possible.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
Execution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2018-19417 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/contiki-ng/contiki-ng/issues/600CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.