This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR Orbi 2.5.1.16 routers.

published 2021-02-11 5 y ago modified 2026-06-17 4 mo ago also EUVD-2020-20354

cvss: 8.8; version 3.0, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 2.1%; EPSS 2.1% chance of exploitation in 30 days, percentile 82%
public exploits: 0; none known

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR Orbi 2.5.1.16 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the UA_Parser utility. A crafted Host Name option in a DHCP request can trigger execution of a system call composed from a user-supplied string. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-11076.

Patch / fix

fixed in 20

netgear cbk40_firmware 2.6.1.38
netgear cbk43_firmware 2.6.1.38
netgear cbr40_firmware 2.6.1.38
netgear ex6200_firmware 1.0.1.82
netgear ex7700_firmware 1.0.0.210
netgear ex8000_firmware 1.0.1.224
netgear rbk12_firmware 2.6.1.44
netgear rbk13_firmware 2.6.1.44
netgear rbk14_firmware 2.6.1.44
netgear rbk15_firmware 2.6.1.44
netgear rbr10_firmware 2.6.1.44
netgear rbs10_firmware 2.6.1.44
netgear rbk20w_firmware 2.6.1.36
netgear rbk23w_firmware 2.6.1.36
netgear rbk20_router_firmware 2.6.1.36
netgear rbk20_satellite_firmware 2.6.1.38
netgear rbk22_router_firmware 2.6.1.36
netgear rbk22_satellite_firmware 2.6.1.38
netgear rbk23_router_firmware 2.6.1.36
netgear rbk23_satellite_firmware 2.6.1.38

Exploit prediction

2.12% chance of exploitation in the next 30 days, higher than 82% of all scored CVEs (FIRST EPSS, 2026-11-08).

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 Orbi

Classification

Weakness

CWE-78 Improper Neutralization of Special Elements used in an OS Command

References

kb.netgear.com /000062507/Security-Advisory-for-Unauthenticated-Command-Injection-Vulnerability-on-Some-Extenders-and-Orbi-Wi
vendor-advisory
zerodayinitiative.com /advisories/ZDI-20-1430/
third-party-advisory, vdb-entry

Sources

CVE List CVE-2020-27861
NVD CVE-2020-27861

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Summary