Security readout for executives and security teams
Plain-English summary
This issue affects NETGEAR XR500 routers running firmware before 2.3.2.32. An unauthenticated attacker on an adjacent network could abuse the traceroute feature to run code on the device. Compromise could expose traffic, alter router settings, or disrupt connectivity.
Executive priority
Prioritize remediation for XR500 routers in shared offices, guest Wi-Fi environments, or networks with untrusted adjacent users. Treat this as a high-priority infrastructure fix, especially where routers support business-critical connectivity.
Technical view
CVE-2018-21117 is a pre-authentication stack overflow leading to remote code execution in the NETGEAR XR500 traceroute handler before firmware 2.3.2.32. CVSS v3.0 is 8.8, with adjacent-network attack vector, low complexity, no privileges, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to NETGEAR XR500 devices on firmware older than 2.3.2.32. The CVSS vector indicates adjacent-network reachability, so risk is highest where untrusted users can reach the router’s local network or management surface.
Exploitation context
The provided bundle does not show CISA KEV listing or cited evidence of active exploitation. The issue remains serious because it is unauthenticated, low complexity, and can affect all three security pillars, but the adjacent-network vector limits attacker positioning compared with broadly internet-reachable flaws.
Researcher notes
The source bundle names XR500 and firmware before 2.3.2.32, but structured affected CPE data is incomplete. Analysis should stay tied to the NETGEAR advisory and CVE record unless additional vendor-confirmed affected models or exploit evidence is obtained.
Mitigation direction
- Upgrade NETGEAR XR500 firmware to 2.3.2.32 or later.
- Review the NETGEAR advisory for vendor-specific guidance.
- Restrict router management access to trusted networks only.
- Segment untrusted Wi-Fi or guest users away from router administration paths.
Validation and detection
- Inventory NETGEAR XR500 devices and record firmware versions.
- Confirm no XR500 runs firmware older than 2.3.2.32.
- Review network segmentation for guest or untrusted adjacent users.
- Check router logs for unusual administrative or diagnostic activity.
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-2018-21117 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
- High
- CVSS
- 8.8 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N
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:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
8.8HighVector: CVSS:3.0/AC:L/AV:A/A:H/C:H/I:H/PR:N/S:U/UI:N
Source materials
- CVE List V5 sourceCVE List V5
- https://kb.netgear.com/000060241/Security-Advisory-for-Pre-Authentication-Stack-Overflow-on-XR500-PSV-2018-0313CVE reference · x_refsource_CONFIRM
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.