This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6020, R6080, R6120, R62…

published 2021-02-11 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-20359

cvss: 8.8; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 8.7%; EPSS 8.7% chance of exploitation in 30 days, percentile 95%
public exploits: 0; none known, plus a Nuclei check

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6020, R6080, R6120, R6220, R6260, R6700v2, R6800, R6900v2, R7450, JNR3210, WNR2020, Nighthawk AC2100, and Nighthawk AC2400 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the mini_httpd service, which listens on TCP port 80 by default. The issue results from incorrect string matching logic when accessing protected pages. An attacker can leverage this in conjunction with other vulnerabilities to execute code in the context of root. Was ZDI-CAN-11355.

Patch / fix

fixed in 19

netgear ac2100_firmware 1.2.0.76
netgear ac2400_firmware 1.2.0.76
netgear ac2600_firmware 1.2.0.76
netgear r6700_firmware 1.2.0.76
netgear r6800_firmware 1.2.0.76
netgear r6900_firmware 1.2.0.76
netgear r7200_firmware 1.2.0.76
netgear r7350_firmware 1.2.0.76
netgear r7400_firmware 1.2.0.76
netgear r7450_firmware 1.2.0.76
netgear r6220_firmware 1.1.0.104
netgear r6230_firmware 1.1.0.104
netgear r6260_firmware 1.1.0.78
netgear r6330_firmware 1.1.0.78
netgear r6350_firmware 1.1.0.78
netgear r6850_firmware 1.1.0.78
netgear r6120_firmware 1.0.0.76
netgear r6020_firmware 1.0.0.48
netgear r6080_firmware 1.0.0.48

Exploit prediction

8.66% chance of exploitation in the next 30 days, higher than 95% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

Nuclei template NETGEAR - Authentication Bypass nuclei detection template

CVSS scores

assigned by	version	score	vector
CNA	3.0	8.8	CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	8.8	CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	8.3	AV:A/AC:L/Au:N/C:C/I:C/A:C

Affected products

NETGEAR Multiple Routers

Classification

Weakness

CWE-288 Authentication Bypass Using an Alternate Path or Channel
CWE-287 Improper Authentication

References

kb.netgear.com /000062641/Security-Advisory-for-Password-Recovery-Vulnerabilities-on-Some-Routers
vendor-advisory
zerodayinitiative.com /advisories/ZDI-20-1451/
third-party-advisory, vdb-entry

Sources

CVE List CVE-2020-27866
NVD CVE-2020-27866

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary