Security readout for executives and security teams
Plain-English summary
This flaw could let someone near the network take control of affected NETGEAR routers without logging in. The vulnerable web service runs as root, so successful compromise could give full device control. The source bundle does not show confirmed active exploitation.
Executive priority
Treat as a high-priority infrastructure hygiene issue for NETGEAR edge and network devices. Prioritize sites where management interfaces are reachable by shared, guest, contractor, or poorly segmented networks.
Technical view
CVE-2021-34982 is a stack-based buffer overflow in NETGEAR router httpd, listening on TCP port 80 by default. Improper length validation while parsing the strings file can allow unauthenticated, network-adjacent code execution as root. CVSS is 8.8 high.
Likely exposure
Exposure is most likely where affected NETGEAR devices are reachable from local or adjacent networks on the default HTTP service. The bundle lists NETGEAR Multiple Routers version V1.0.11.116_10.2.100, but product coverage should be verified against NETGEAR advisory PSV-2021-0159.
Exploitation context
Authentication is not required, user interaction is not required, and attack complexity is low. The CVSS vector is adjacent-network, not internet-wide by default. KEV is false, and the provided sources do not establish active exploitation.
Researcher notes
The source evidence supports unauthenticated adjacent-network RCE through httpd and CWE-121. The exact model matrix and fixed firmware versions are not included in the bundle text, so vendor advisory review is required before scoping remediation.
Mitigation direction
- Check NETGEAR advisory PSV-2021-0159 for affected models and fixed firmware.
- Apply vendor-provided firmware updates for confirmed affected devices.
- Restrict access to TCP port 80 management interfaces to trusted administrators.
- Segment router management access away from guest and untrusted networks.
- Replace devices if no supported fixed firmware is available.
Validation and detection
- Inventory NETGEAR routers, extenders, and DSL modem routers in use.
- Record model numbers and firmware versions for each device.
- Compare firmware against NETGEAR advisory PSV-2021-0159.
- Confirm TCP port 80 management access is not reachable from untrusted networks.
- Review device and network telemetry for unexpected management-interface access.
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-121: 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 lookupExecution 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-2021-34982 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/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/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:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H2.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
8.8HighVector: CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- ZDI-21-1274CVE reference · x_research-advisory
- vendor-provided URLCVE reference · vendor-advisory
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.
Stack-based Buffer Overflow
Stack-based Buffer Overflow represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.