CyberSecBulletin
CVE-2024-39948NVD status: Modified

NVR4XXX: NULL Pointer Dereference

Published Updated By the CyberSecBulletin desk

CVE-2024-39948 is a high-severity NULL pointer dereference vulnerability in NVR4XXX from Dahua, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected NVR4XXX versions: NVR4XXX Versions which Build time before 2023/12/13. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.56% 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 nvr4832-i to 2023.12.13 or a later version.
  2. Update Nvr4104-4ks2/l Firmware to 4.003.0000000.1.r.240515 or a later version.
  3. Update Nvr4116-4ks2/l Firmware to 4.003.0000000.1.r.240515 or a later version.
  4. Read the advisory on dahuasecurity.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
DahuaNVR4XXXNVR4XXX Versions which Build time before 2023/12/13Not stated
Dahuasecuritynvr4832-ibefore 2023.12.132023.12.13
DahuasecurityNvr4104-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4108-4ks2/l Firmware4.003.0000000.1.r.240515Not stated
DahuasecurityNvr4116-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4104-p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4108-p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4108-8p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4116-8p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4104hs-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4108hs-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4104hs-p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4108hs-p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4108hs-8p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4116hs-8p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4204-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4208-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4216-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4204-p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4208-8p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4216-16p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4232-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4232-16p-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4116hs-4ks2/l Firmwarebefore 4.003.0000000.1.r.2405154.003.0000000.1.r.240515
DahuasecurityNvr4416-4ks2/i Firmwarebefore 4.001.0000001.6.r.2407254.001.0000001.6.r.240725

Version data comes from the organisation that assigned the CVE; 33 further products are omitted here. 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
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighCNA (dahuatech.com)
CVSS 3.17.5HighNVD

Official description

A vulnerability has been found in Dahua products. Attackers can send carefully crafted data packets to the interface with vulnerabilities, causing the device to crash.

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

The underlying weakness: NULL Pointer Dereference

The product dereferences a pointer that it expects to be valid but is NULL.

How developers prevent this class of flaw

  • For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished.
  • Select a programming language that is not susceptible to these issues.
  • Check the results of all functions that return a value and verify that the value is non-null before acting upon it.

More NULL Pointer Dereference vulnerabilities (CWE-476)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in NVR4XXX

All NVR4XXX vulnerabilities

Recent NULL Pointer Dereference vulnerabilities

Spotted an error? Tell us.