CyberSecBulletin
CVE-2021-33045Exploited in the wildNVD status: Analyzed

Dahua IP Camera Authentication Bypass

Published Updated By the CyberSecBulletin desk

CVE-2021-33045 is a critical-severity improper authentication vulnerability in Some Dahua IP Camera, Video Intercom, NVR, XVR devices, 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. CISA added it to the Known Exploited Vulnerabilities catalogue on August 21, 2024, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Ipc-hum7xxx Firmware to 2.820.0000000.5.r.210705 or a later version.
  2. Update Ipc-hx3xxx Firmware to 2.800.0000000.29.r.210630 or a later version.
  3. Update Ipc-hx5xxx Firmware to 2.820.0000000.5.r.210705 or a later version.
  4. CISA's required action: Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
  5. Read the advisory on dahuasecurity.com for workarounds and exact fixed builds.
  6. 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
Some Dahua IP Camera, Video Intercom, NVR, XVR devicesSome Dahua IP Camera, Video Intercom, NVR, XVR devicesNot specified in the recordNot stated
DahuasecurityIpc-hum7xxx Firmwarebefore 2.820.0000000.5.r.2107052.820.0000000.5.r.210705
DahuasecurityIpc-hx3xxx Firmwarebefore 2.800.0000000.29.r.2106302.800.0000000.29.r.210630
DahuasecurityIpc-hx5xxx Firmwarebefore 2.820.0000000.5.r.2107052.820.0000000.5.r.210705
DahuasecurityNvr-1xxx Firmwarebefore 4.001.0000005.1.r.2107094.001.0000005.1.r.210709
DahuasecurityNvr-2xxx Firmwarebefore 4.001.0000000.1.r.2107104.001.0000000.1.r.210710
DahuasecurityNvr-4xxx Firmwarebefore 4.001.0000005.1.r.2107134.001.0000005.1.r.210713
DahuasecurityNvr-5xxx Firmwarebefore 4.001.0000000.0.r.2107104.001.0000000.0.r.210710
DahuasecurityNvr-6xx Firmwarebefore 4.001.0000001.1.r.2107164.001.0000001.1.r.210716
DahuasecurityVth-542xh Firmwarebefore 4.500.0000002.0.r.2107154.500.0000002.0.r.210715
DahuasecurityVto-65xxx Firmwarebefore 4.300.0000004.0.r.2107154.300.0000004.0.r.210715
DahuasecurityVto-75x95x Firmwarebefore 4.300.0000003.0.r.2107144.300.0000003.0.r.210714
DahuasecurityXvr-4x04 Firmwarebefore 4.001.0000001.1.r.2107094.001.0000001.1.r.210709
DahuasecurityXvr-4x08 Firmwarebefore 4.001.0000001.1.r.2107094.001.0000001.1.r.210709
DahuasecurityXvr-5x04 Firmwarebefore 4.001.0000003.1.r.2107104.001.0000003.1.r.210710
DahuasecurityXvr-5x08 Firmwarebefore 4.001.0000003.1.r.2107104.001.0000003.1.r.210710
DahuasecurityXvr-5x16 Firmwarebefore 4.001.0000003.1.r.2107104.001.0000003.1.r.210710
DahuasecurityXvr-7x16 Firmwarebefore 4.001.0000003.1.r.2107104.001.0000003.1.r.210710
DahuasecurityXvr-7x32 Firmwarebefore 4.001.0000003.1.r.2107104.001.0000003.1.r.210710

Version data comes from the organisation that assigned the CVE. 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.

Scoring systemScoreSeverityScored by
CVSS 3.19.8CriticalNVD
CVSS 3.19.8CriticalCISA (ADP)
CVSS 2.010.0HighNVD

Official description

The identity authentication bypass vulnerability found in some Dahua products during the login process. Attackers can bypass device identity authentication by constructing malicious data packets.

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

The underlying weakness: Improper Authentication

When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.

How developers prevent this class of flaw

  • Use an authentication framework or library such as the OWASP ESAPI Authentication feature.

More Improper Authentication vulnerabilities (CWE-287)

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. CISA published its SSVC assessment (exploitation: active, automatable: yes, technical impact: total).
  4. Deadline for US federal agencies to remediate, set by CISA.
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Technical write-ups (may include proof of concept)

Recent Improper Authentication vulnerabilities

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