CyberSecBulletin
CVE-2022-40620NVD status: Analyzed

Rbr20 Firmware: Improper Certificate Validation

Published Updated By the CyberSecBulletin desk

CVE-2022-40620 is a high-severity improper certificate validation vulnerability in Rbr20 Firmware from NETGEAR, with a CVSS 3.1 base score of 7.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 2.7.2.26 as the first without the flaw, so updating Rbr20 Firmware to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.32% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Rbr20 Firmware to 2.7.2.26 or a later version.
  2. Update R6230 Firmware to 1.1.0.112 or a later version.
  3. Update R6260 Firmware to 1.1.0.88 or a later version.
  4. Read the advisory on kb.netgear.com for workarounds and exact fixed builds.
  5. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
NETGEARRbr20 Firmwarebefore 2.7.2.262.7.2.26
NETGEARR6230 Firmwarebefore 1.1.0.1121.1.0.112
NETGEARR6260 Firmwarebefore 1.1.0.881.1.0.88
NETGEARR7000 Firmwarebefore 1.0.11.1341.0.11.134
NETGEARR8900 Firmwarebefore 1.0.5.421.0.5.42
NETGEARR9000 Firmwarebefore 1.0.5.421.0.5.42
NETGEARRax120 Firmwarebefore 1.2.8.401.2.8.40
NETGEARRax120v2 Firmwarebefore 1.2.8.401.2.8.40
NETGEARXr300 Firmwarebefore 1.0.3.721.0.3.72
NETGEARRbs20 Firmwarebefore 2.7.2.262.7.2.26

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:L. Scored by CISA (ADP).

Official description

FunJSQ, a third-party module integrated on some NETGEAR routers and Orbi WiFi Systems, does not properly validate TLS certificates when downloading update packages through its auto-update mechanism. An attacker (suitably positioned on the network) could intercept the update request and deliver a malicious update package in order to gain arbitrary code execution on affected devices. This affects R6230 before 1.1.0.112, R6260 before 1.1.0.88, R7000 before 1.0.11.134, R8900 before 1.0.5.42, R9000 before 1.0.5.42, and XR300 before 1.0.3.72 and Orbi RBR20 before 2.7.2.26, RBR50 before 2.7.4.26, RBS20 before 2.7.2.26, and RBS50 before 2.7.4.26.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Certificate Validation

The product does not validate, or incorrectly validates, a certificate.

How developers prevent this class of flaw

  • Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
  • If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

More Improper Certificate Validation vulnerabilities (CWE-295)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Rbr20 Firmware

All Rbr20 Firmware vulnerabilities

Recent Improper Certificate Validation vulnerabilities

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