What is CVE-2021-34978?

CVE-2021-34978 is a high-severity vulnerability in NETGEAR R6260, classified under Stack-based Buffer Overflow. CVSS score: 8.8/10. Published 2022-01-13.

How severe is CVE-2021-34978?

High severity. CVSS v3 base score is 8.8 out of 10.

Buffer overflow in NETGEAR R6260

CVE-2021-34978

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6260 1.1.0.78_1.0.1 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the setupwizard.cgi page. A crafted SOAP request can trigger an overflow of a fixed-length stack-based buffer. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-13511.

Vulnerability class: Buffer Overflow

Published 2022-01-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.015 (73.6th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 74th percentile — 73.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.015 · newest: 0.015 · change: 0.000

Affected products

NETGEAR R6260 — versions 1.1.0.78_1.0.1
NETGEAR R6260 Firmware — versions 1.1.0.78_1.0.1

Weakness classification (CWE)

References

www.zerodayinitiative.com/advisories/ZDI-21-1240/ (VDB Entry, Third Party Advisory)
kb.netgear.com/000064258/Security-Advisory-for-Vertical-Privilege-Escalation-on… (Vendor Advisory)

Frequently asked questions

What is CVE-2021-34978?: CVE-2021-34978 is a high-severity vulnerability in NETGEAR R6260, classified under Stack-based Buffer Overflow. CVSS score: 8.8/10. Published 2022-01-13.
How severe is CVE-2021-34978?: High severity. CVSS v3 base score is 8.8 out of 10.