Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2021-33044

Some Dahua IP Camera Authentication Bypass

Dahua / Some Dahua IP Camera · Dahua IP Camera devices IPC-HX3XXX, IPC-HX5XXX, and IPC-HUM7XXX, Video Intercom devices VTO75X95X, VTO65XXX, and VTH542XH, PTZ Dome Camera SD1A1, SD22, SD49, SD50, SD52C, and SD6AL, Thermal TPC-BF1241, TPC-BF2221, TPC-SD2221, TPC-BF5XXX, TPC-SD8X21, and TPC-PT8X21B devices Buildtime before June, 2021.

Watch CVE-2021-33044 Browse KEV feed
Severity
CVSS 9.8 · Critical
Confidence
Confirmed
Exploit status
Exploited in the wild
EPSS
100.0%
First observed
—
Last observed
—

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2021-33044 is an unauthenticated vulnerability affecting Dahua Some Dahua IP Camera and 3 other products. The identity authentication bypass vulnerability found in some Dahua products during the login process....

Is it exploited?

Yes. Previdian tracks this CVE as a known exploited vulnerability. Confidence is confirmed. Listed in CISA KEV. Also confirmed by third-party sources.

Who is affected?

Dahua / Some Dahua IP Camera dahua ip camera devices ipc-hx3xxx, ipc-hx5xxx, and ipc-hum7xxx, video intercom devices vto75x95x, vto65xxx, and vth542xh, ptz dome camera sd1a1, sd22, sd49, sd50, sd52c, and sd6al, thermal tpc-bf1241, tpc-bf2221, tpc-sd2221, tpc-bf5xxx, tpc-sd8x21, and tpc-pt8x21b devices buildtime before june, 2021..

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

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

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.

n/a Affected
Some Dahua IP Camera, Video Intercom, PTZ Dome Camera, Thermal Camera devices
Dahua IP Camera devices IPC-HX3XXX, IPC-HX5XXX, and IPC-HUM7XXX, Video Intercom devices VTO75X95X, VTO65XXX, and VTH542XH, PTZ Dome Camera SD1A1, SD22, SD49, SD50, SD52C, and SD6AL, Thermal TPC-BF1241, TPC-BF2221, TPC-SD2221, TPC-BF5XXX, TPC-SD8X21, and TPC-PT8X21B devices Buildtime before June, 2021.
Published
15 Sep 2021
Exploitation Reported
21 Aug 2024
Attack vector
Remote
Complexity
Low
Privileges
None
User interaction
None

Tags

nuclei_scanner cisa nessus_scanner

CVE References

Exploitation evidence

Why Previdian marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 21 Aug 2024

A trusted third party reported exploitation.

Proof of concept available

GitHub

Recorded 18 Oct 2021

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the Previdian Pro API.

Learn about Pro API access
Source Added
CISA First 2024-08-21 00:00 UTC
The Shadowserver 2026-07-08 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
User-Agents
Callback hosts
0
0
0

Request targets and User-Agents available in Pro. Callback host details available in Enterprise.

Virtual patch status

No Previdian virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Scanner Reference Detected
Nuclei https://github.com/projectdiscovery/nuclei-templates/blob/main/http/cves/2021/CVE-2021-33044.yaml 25 Apr 2025

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

9.8 Critical

Potential damage if exploited. Separate from whether attackers are using it.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

100.0%

Estimated chance of exploitation in the next 30 days. Previdian's warning comes from evidence, not this score.

Weaknesses

Improper Authentication CWE-287

Recent mention · The Hacker News

Human Attacker Exploits Marimo RCE, Reaches SSH Bastion in Eight Seconds

With artificial intelligence (AI) shrinking the window between vulnerability discovery and exploitation and lowering the barrier to entry for bad actors, new findings from Sysdig show that skilled human operators can move just as swiftly after gaining initial access. In one...

Read full advisory

All CVSS Scores

CVSS v3.1 9.8 Critical

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CVSS v2.0 10.0 High

AV:N/AC:L/Au:N/C:C/I:C/A:C

All Mentions

Recent mention · The Hacker News

Human Attacker Exploits Marimo RCE, Reaches SSH Bastion in Eight Seconds

The Hacker News · 15 Sep 2026

With artificial intelligence (AI) shrinking the window between vulnerability discovery and exploitation and lowering the barrier to entry for bad actors, new findings from Sysdig show that skilled human operators can move just as swiftly after gaining initial access. In one instance highlighted by the cloud security company, the threat actor pivoted from a vulnerable Marimo notebook to an SSH

Recent mention · RecordedFuture

August 2026 CVE Landscape

RecordedFuture · 08 Sep 2026

In August 2026, Insikt Group® identified 73 high-impact vulnerabilities that should be prioritized for remediation, 43 of which had a Very Critical Recorded Future Risk Score. This represents a 14% decrease from last month.

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Dahua IPC/VTH/VTO - Authentication Bypass

nuclei · Created Unknown

Timeline

From disclosure to observed exploitation

  1. 00:00 UTC

    KEV confirmed by The Shadowserver

    Exploitation attested by an external source

  2. 14:20 UTC

    Public PoC available

    Public proof-of-concept code published

  3. 00:00 UTC

    Nuclei template available

    Scanner coverage available

  4. 00:00 UTC

    Added to CISA KEV

    Listed in the CISA Known Exploited Vulnerabilities catalog

  5. 21:36 UTC

    CVE published

    Vulnerability disclosed publicly

  6. 00:00 UTC

    CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

Start 14-day Pro trial Read API docs
  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2021-33044

Sample API response 
{
  "cve_id": "CVE-2021-33044",
  "confidence": "Confirmed",
  "cvss_score": 9.8,
  "cvss_estimated": false,
  "epss_score": 0.99989,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}