CyberSecBulletin
CVE-2022-28935NVD status: Modified

A830r Firmware: Improper Neutralization of Special Elements used in a Command

Published Updated By the CyberSecBulletin desk

CVE-2022-28935 is a high-severity improper neutralization of special elements used in a command vulnerability in A830r Firmware from TOTOLINK, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected A830r Firmware versions: 5.9c.4729_b20191112. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 3.3% chance of exploitation within 30 days, higher than 89% of scored CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of A830r Firmware you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
TOTOLINKA830r Firmware5.9c.4729_b20191112Not stated
TOTOLINKA3100r Firmware4.1.2cu.5050_b20200504Not stated
TOTOLINKA950rg Firmware4.1.2cu.5161_b20200903Not stated
TOTOLINKA800r Firmware4.1.2cu.5137_b20200730Not stated
TOTOLINKA3000ru Firmware5.9c.5185_b20201128Not stated
TOTOLINKA810r Firmware4.1.2cu.5182_b20201026Not stated

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
LowNo special conditions are needed; the attack works reliably.
Privileges required
HighAdministrator-level access is required first.
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:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.2HighNVD
CVSS 2.06.5MediumNVD

Official description

Totolink A830R V5.9c.4729_B20191112, Totolink A3100R V4.1.2cu.5050_B20200504, Totolink A950RG V4.1.2cu.5161_B20200903, Totolink A800R V4.1.2cu.5137_B20200730, Totolink A3000RU V5.9c.5185_B20201128, Totolink A810R V4.1.2cu.5182_B20201026 were discovered to contain a command injection vulnerability.

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 a Command

The product constructs all or part of a command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended command when 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.
  • If possible, ensure that all external commands called from the program are statically created.
  • Run time: Run time policy enforcement may be used in an allowlist fashion to prevent use of any non-sanctioned commands.

More Improper Neutralization of Special Elements used in a Command vulnerabilities (CWE-77)

Timeline

  1. CVE record published.
  2. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in A830r Firmware

All A830r Firmware vulnerabilities

Recent Improper Neutralization of Special Elements used in a Command vulnerabilities

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