CyberSecBulletin
CVE-2022-37134NVD status: Modified

Dir-816 Firmware: Improper Validation of Specified Quantity in Input

Published Updated By the CyberSecBulletin desk

CVE-2022-37134 is a critical-severity improper validation of specified quantity in input vulnerability in Dir-816 Firmware from D-Link, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Dir-816 Firmware versions: 1.10cnb04. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 22.3% chance of exploitation within 30 days, which is in the top 2.28% of all scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Dir-816 Firmware you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on dlink.com for workarounds and exact fixed builds.
  3. 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
D-LinkDir-816 Firmware1.10cnb04Not 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
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:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Official description

D-link DIR-816 A2_v1.10CNB04.img is vulnerable to Buffer Overflow via /goform/form2Wan.cgi. When wantype is 3, l2tp_usrname will be decrypted by base64, and the result will be stored in v94, which does not check the size of l2tp_usrname, resulting in stack overflow.

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

The underlying weakness: Improper Validation of Specified Quantity in Input

The product receives input that is expected to specify a quantity (such as size or length), but it does not validate or incorrectly validates that the quantity has the required properties.

More Improper Validation of Specified Quantity in Input vulnerabilities (CWE-1284)

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 Dir-816 Firmware

All Dir-816 Firmware vulnerabilities

Recent Improper Validation of Specified Quantity in Input vulnerabilities

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