CyberSecBulletin
CVE-2022-27647NVD status: Modified

R6700v3: Improper Neutralization of Special Elements used in an OS Command

Published Updated By the CyberSecBulletin desk

CVE-2022-27647 is a high-severity improper neutralization of special elements used in an OS command vulnerability in R6700v3 from NETGEAR, with a CVSS 3.1 base score of 8.0 out of 10. It can be exploited from the same local network by an attacker with a low-privileged account, 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 1.48% chance of exploitation within 30 days, higher than 74% 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
LowA basic user account is enough.
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:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.18.0HighNVD
CVSS 3.08.0HighCNA (trendmicro.com)

Official description

This vulnerability allows network-adjacent attackers to execute arbitrary code on affected installations of NETGEAR R6700v3 1.0.4.120_10.0.91 routers. Although authentication is required to exploit this vulnerability, the existing authentication mechanism can be bypassed. The specific flaw exists within the handling of the name or email field provided to libreadycloud.so. The issue results from the lack of proper validation of a user-supplied string before using it to execute a system call. An attacker can leverage this vulnerability to execute code in the context of root. Was ZDI-CAN-15874.

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

The underlying weakness: Improper Neutralization of Special Elements used in an OS Command

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command before it is sent to a downstream component.

How developers prevent this class of flaw

  • If at all possible, use library calls rather than external processes to recreate the desired functionality.
  • For any data that will be used to generate a command to be executed, keep as much of that data out of external control as possible. For example, in web applications, this may require storing the data locally in the session's state instead of sending it out to the client in a hidden form field.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Improper Neutralization of Special Elements used in an OS Command vulnerabilities (CWE-78)

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

Third-party and government advisories

Other vulnerabilities in R6700v3

All R6700v3 vulnerabilities

Recent Improper Neutralization of Special Elements used in an OS Command vulnerabilities

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