CyberSecBulletin
CVE-2022-27642NVD status: Modified

R6700v3: Incorrect Authorization

Published Updated By the CyberSecBulletin desk

CVE-2022-27642 is a high-severity incorrect authorization vulnerability in R6700v3 from NETGEAR, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited from the same local network by an unauthenticated attacker, without any action from a user. Affected R6700v3 versions: 1.0.4.120_10.0.91. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.88% chance of exploitation within 30 days, higher than 60% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Cax80 Firmware to 2.1.3.7 or a later version.
  2. Update Lax20 Firmware to 1.1.6.34 or a later version.
  3. Update Mr60 Firmware to 1.1.6.124 or a later version.
  4. Read the advisory on kb.netgear.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
NETGEARR6700v31.0.4.120_10.0.91Not stated
NETGEARCax80 Firmwarebefore 2.1.3.72.1.3.7
NETGEARLax20 Firmwarebefore 1.1.6.341.1.6.34
NETGEARMr60 Firmwarebefore 1.1.6.1241.1.6.124
NETGEARMr80 Firmwarebefore 1.1.6.141.1.6.14
NETGEARMs60 Firmwarebefore 1.1.6.1241.1.6.124
NETGEARMs80 Firmwarebefore 1.1.6.141.1.6.14
NETGEARR6400 Firmwarebefore 1.0.1.78; before 1.0.4.1261.0.1.78, 1.0.4.126
NETGEARR6700 Firmwarebefore 1.0.4.1261.0.4.126
NETGEARR6900p Firmwarebefore 1.3.3.1481.3.3.148
NETGEARR7000 Firmwarebefore 1.0.11.1341.0.11.134
NETGEARR7000p Firmwarebefore 1.3.3.1481.3.3.148
NETGEARR7850 Firmwarebefore 1.0.5.841.0.5.84
NETGEARR7900p Firmwarebefore 1.4.3.881.4.3.88
NETGEARR7960p Firmwarebefore 1.4.3.881.4.3.88
NETGEARR8000 Firmwarebefore 1.0.4.841.0.4.84
NETGEARR8000p Firmwarebefore 1.4.3.881.4.3.88
NETGEARR8500 Firmwarebefore 1.0.2.1581.0.2.158
NETGEARRax15 Firmwarebefore 1.0.10.1101.0.10.110
NETGEARRax20 Firmwarebefore 1.0.10.1101.0.10.110
NETGEARRax200 Firmwarebefore 1.0.6.1381.0.6.138
NETGEARRax35 Firmwarebefore 1.0.10.1101.0.10.110
NETGEARRax38 Firmwarebefore 1.0.10.1101.0.10.110
NETGEARRax40 Firmwarebefore 1.0.10.1101.0.10.110
NETGEARRax42 Firmwarebefore 1.0.10.1101.0.10.110

Version data comes from the organisation that assigned the CVE; 9 further products are omitted here. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
AdjacentThe attacker must be on the same local network segment.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
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
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.18.8HighNVD
CVSS 3.06.3MediumCNA (trendmicro.com)

Official description

This vulnerability allows network-adjacent attackers to bypass authentication on affected installations of NETGEAR R6700v3 1.0.4.120_10.0.91 routers. Authentication is not required to exploit this vulnerability. The specific flaw exists within the httpd service. 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-15854.

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

The underlying weakness: Incorrect Authorization

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check.

How developers prevent this class of flaw

  • Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) to enforce the roles at the appropriate boundaries. Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
  • Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using authorization frameworks such as the JAAS Authorization Framework and the OWASP ESAPI Access Control feature.

More Incorrect Authorization vulnerabilities (CWE-863)

Timeline

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

References

Third-party and government advisories

Other vulnerabilities in R6700v3

All R6700v3 vulnerabilities

Recent Incorrect Authorization vulnerabilities

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