Security readout for executives and security teams
Plain-English summary
CVE-2019-20739 affects NETGEAR R8500 routers running firmware before v1.0.2.128. An unauthenticated attacker on an adjacent network could trigger a buffer overflow. The published impact is limited to low availability impact, with no stated confidentiality or integrity impact.
Executive priority
Treat this as a targeted router hygiene issue, not an emergency. Prioritize affected R8500 devices in shared, guest, branch, or unmanaged networks where adjacent access is plausible.
Technical view
This is a pre-authentication buffer overflow in NETGEAR R8500 firmware before v1.0.2.128. CVSS 3.0 is 4.3: adjacent network attack vector, low complexity, no privileges, no user interaction, unchanged scope, and low availability impact only.
Likely exposure
Exposure is most likely in environments still operating NETGEAR R8500 devices below firmware v1.0.2.128, especially where untrusted users can reach the same local or adjacent network segment.
Exploitation context
The source bundle does not show CISA KEV listing or cited active exploitation. The CVSS vector indicates an adjacent-network attacker, not a broadly remote Internet attack path based on the provided evidence.
Researcher notes
Affected product data in the CVE record is sparse, but the title, description, and NETGEAR advisory identify R8500 before v1.0.2.128. No CWE, exploit details, or broader model list is provided in the bundle.
Mitigation direction
- Update NETGEAR R8500 firmware to v1.0.2.128 or later.
- Review the NETGEAR advisory for current vendor instructions.
- Limit untrusted access to local or adjacent router network segments.
- Replace unsupported or unmanaged R8500 devices if updates cannot be confirmed.
Validation and detection
- Inventory NETGEAR R8500 devices across offices, labs, and remote sites.
- Check each device firmware version against v1.0.2.128.
- Confirm network segmentation limits adjacent access to the router.
- Document remediation status and exceptions for asset owners.
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.
CVE-2019-20739 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
- 4.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AC:L/AV:A/A:L/C:N/I:N/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:L/C:N/I:N/PR:N/S:U/UI:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
4.3MediumVector: CVSS:3.0/AC:L/AV:A/A:L/C:N/I:N/PR:N/S:U/UI:N
Source materials
- CVE List V5 sourceCVE List V5
- https://kb.netgear.com/000061179/Security-Advisory-for-Pre-Authentication-Buffer-Overflow-on-R8500-PSV-2017-0636CVE 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.