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Fencer Vulns
critical 9.8

CVE-2021-33045 kev in the critical feed json

The identity authentication bypass vulnerability found in some Dahua products during the login process.

published 2021-09-15 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-19760

cvss
9.8
version 3.1, CNA
cisa kev
Exploited
added 2024-08-21
epss
99.6%
EPSS 99.6% chance of exploitation in 30 days, percentile 99.9%
public exploits
0
none known, plus a Nuclei check

Summary

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.

Patch / fix

cisa required action Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

  • dahuasecurity ipc-hum7xxx_firmware 2.820.0000000.5.r.210705
  • dahuasecurity ipc-hx3xxx_firmware 2.800.0000000.29.r.210630
  • dahuasecurity ipc-hx5xxx_firmware 2.820.0000000.5.r.210705
  • dahuasecurity nvr-1xxx_firmware 4.001.0000005.1.r.210709
  • dahuasecurity nvr-2xxx_firmware 4.001.0000000.1.r.210710
  • dahuasecurity nvr-4xxx_firmware 4.001.0000005.1.r.210713
  • dahuasecurity nvr-5xxx_firmware 4.001.0000000.0.r.210710
  • dahuasecurity nvr-6xx_firmware 4.001.0000001.1.r.210716
  • dahuasecurity vth-542xh_firmware 4.500.0000002.0.r.210715
  • dahuasecurity vto-65xxx_firmware 4.300.0000004.0.r.210715
  • dahuasecurity vto-75x95x_firmware 4.300.0000003.0.r.210714
  • dahuasecurity xvr-4x08_firmware 4.001.0000001.1.r.210709
  • dahuasecurity xvr-4x04_firmware 4.001.0000001.1.r.210709
  • dahuasecurity xvr-5x04_firmware 4.001.0000003.1.r.210710
  • dahuasecurity xvr-5x08_firmware 4.001.0000003.1.r.210710
  • dahuasecurity xvr-5x16_firmware 4.001.0000003.1.r.210710
  • dahuasecurity xvr-7x16_firmware 4.001.0000003.1.r.210710
  • dahuasecurity xvr-7x32_firmware 4.001.0000003.1.r.210710

Timeline

  1. Published
  2. Added to CISA KEV
  3. CISA SSVC: exploitation active
  4. CISA patch deadline

Known exploited

Added
2 y ago
Patch by
2024-09-11 (2 y ago)
Ransomware
Not known
Required action
Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
Vendor, product
Dahua, IP Camera Firmware
CISA name
Dahua IP Camera Authentication Bypass Vulnerability

CISA SSVC

Exploitation
Active, exploited in the wild
Automatable
yes
Technical impact
total
Assessed
2 y ago

Exploit prediction

99.59% chance of exploitation in the next 30 days, higher than 99.9% of all scored CVEs (FIRST EPSS, 2026-11-08).

Exploits and checks

  • Nuclei template Dahua IPC/VTH/VTO - Authentication Bypass nuclei detection template
  • seclists.org http://seclists.org/fulldisclosure/2021/Oct/13 referenced PoC, tagged "exploit" by a source, unverified
  • packetstormsecurity.com http://packetstormsecurity.com/files/164423/Dahua-Authentication-Bypass.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CISA ADP 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA 3.1 9.8 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD 2.0 10.0 AV:N/AC:L/Au:N/C:C/I:C/A:C

Affected products

  • n/a Some Dahua IP Camera, Video Intercom, NVR, XVR devices

Classification

Weakness

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.