Security readout for executives and security teams
Plain-English summary
This flaw can let a remote, unauthenticated attacker crash or disrupt affected embedded network devices by sending a specially crafted network packet. It affects Weston Embedded uC-TCP-IP v3.06.01 and Silicon Labs Gecko Platform 4.3.1.0 as listed in the source bundle.
Executive priority
Treat this as a targeted availability risk for embedded systems, not a data theft issue. Prioritize exposed or business-critical devices, especially where downtime affects operations, safety, or customer service.
Technical view
CVE-2023-39540 is a CWE-126 out-of-bounds read in ICMP and ICMPv6 parsing, specifically described for IPv4 ICMP packet handling. CVSS 3.1 is 5.9: network reachable, high attack complexity, no privileges or user interaction, with availability impact only.
Likely exposure
Exposure is most likely in embedded or IoT products using Weston Embedded uC-TCP-IP v3.06.01 or Silicon Labs Gecko Platform 4.3.1.0 where ICMP traffic can reach the device.
Exploitation context
The bundle says an attacker can send a malicious packet to trigger denial of service. It does not cite public exploitation, and CISA KEV status is false, so active exploitation is not established here.
Researcher notes
The provided evidence supports denial of service through an out-of-bounds read in ICMP parsing. Sources do not provide confirmed patch details or exploitation in the wild, so validation should focus on version exposure and reachable ICMP attack surface.
Mitigation direction
- Inventory products and firmware using the affected network stack versions.
- Check Weston Embedded and Silicon Labs guidance for fixed releases or vendor workarounds.
- Restrict ICMP and ICMPv6 exposure from untrusted networks where operationally safe.
- Segment affected embedded devices away from direct internet or hostile network access.
- Prioritize remediation for devices supporting critical operations or remote connectivity.
Validation and detection
- Confirm whether deployed firmware includes uC-TCP-IP v3.06.01 or Gecko Platform 4.3.1.0.
- Map which affected devices accept ICMP or ICMPv6 from untrusted network paths.
- Review logs for unexplained crashes, watchdog resets, or availability loss around network events.
- Verify boundary controls limit unnecessary ICMP and ICMPv6 reachability to affected devices.
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.
CWE-126: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2023-39540 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
- Medium
- CVSS
- 5.9 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
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 vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H2.23.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.9MediumVector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
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.
Buffer Over-read
Buffer Over-read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.