CVE Intelligence
CISA KEV Critical Authentication exploit reference

CVE-2021-33045 — Dahua IP Camera Authentication Bypass Vulnerability

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.

Published Sep 15, 2021 · Updated Oct 13, 2026 · Sources: CISA Known Exploited Vulnerabilities, NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: dahua

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

How the score was calculated
  • Confirmed exploitation (CISA KEV)+35
  • Public exploit/PoC (nuclei, github)+10
  • EPSS 99.6% (30-day exploitation probability)+15
  • Technical severity (critical)+10
  • Automatable exploitation (SSVC)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Confirmed
CISA KEV, listed Aug 21, 2024
EPSS FIRST
99.59%
ahead of 100% of scored CVEs · Oct 14, 2026
Affects
Dahuasecurity
Ipc-hum7xxx Firmware and 17 more
CVSS base
9.8
Critical · 4 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Active
none · proof-of-concept · active
Automatable
Yes
can an attacker script the kill-chain steps
Technical impact
Total
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

CISA required action CISA

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

US federal deadline: Sep 11, 2024 — passed 764 day(s) ago

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Dahuasecurity Ipc-hum7xxx Firmware, Dahuasecurity Ipc-hx3xxx Firmware, Dahuasecurity Ipc-hx5xxx Firmware…).
  2. Treat as emergency remediation: the CVE is in CISA KEV (confirmed exploitation).
  3. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  4. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  5. EPSS ahead of 100% of scored CVEs: prioritize it in the patch queue.
  6. Search available logs for exploit probes matching the vulnerability class (authentication), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Dahuasecurity Ipc-hum7xxx Firmware < 2.820.0000000.5.r.210705 Vulnerable NIST National Vulnerability Database
Dahuasecurity Ipc-hx3xxx Firmware < 2.800.0000000.29.r.210630 Vulnerable NIST National Vulnerability Database
Dahuasecurity Ipc-hx5xxx Firmware < 2.820.0000000.5.r.210705 Vulnerable NIST National Vulnerability Database
Dahuasecurity Nvr-1xxx Firmware < 4.001.0000005.1.r.210709 Vulnerable NIST National Vulnerability Database
Dahuasecurity Nvr-2xxx Firmware < 4.001.0000000.1.r.210710 Vulnerable NIST National Vulnerability Database
Dahuasecurity Nvr-4xxx Firmware < 4.001.0000005.1.r.210713 Vulnerable NIST National Vulnerability Database
Dahuasecurity Nvr-5xxx Firmware < 4.001.0000000.0.r.210710 Vulnerable NIST National Vulnerability Database
Dahuasecurity Nvr-6xx Firmware < 4.001.0000001.1.r.210716 Vulnerable NIST National Vulnerability Database
Dahuasecurity Vth-542xh Firmware < 4.500.0000002.0.r.210715 Vulnerable NIST National Vulnerability Database
Dahuasecurity Vto-65xxx Firmware < 4.300.0000004.0.r.210715 Vulnerable NIST National Vulnerability Database
Dahuasecurity Vto-75x95x Firmware < 4.300.0000003.0.r.210714 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-4x04 Firmware versions not specified by the source< 4.001.0000001.1.r.210709 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-4x08 Firmware < 4.001.0000001.1.r.210709 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-5x04 Firmware < 4.001.0000003.1.r.210710 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-5x08 Firmware < 4.001.0000003.1.r.210710 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-5x16 Firmware < 4.001.0000003.1.r.210710 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-7x16 Firmware < 4.001.0000003.1.r.210710 Vulnerable NIST National Vulnerability Database
Dahuasecurity Xvr-7x32 Firmware < 4.001.0000003.1.r.210710 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
9.8 CVSS 3.1 Critical 3.9 5.9 nvd@nist.gov via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical 3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0 via NIST National Vulnerability Database
9.8 CVSS 3.1 Critical — — GitHub, Inc. via GitHub Security Advisories
9.8 CVSS 3.1 Critical — — CISA-ADP via CVE Program (cve.org) e CISA ADP
10.0 CVSS 2.0 High 10.0 10.0 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-287 · Improper Authentication

Other CVEs with this weakness →

CISA KEV details CISA

CISA lists a CVE once it has evidence of exploitation against real targets.

Listed
Aug 21, 2024
Federal deadline
Sep 11, 2024
passed 764 day(s) ago
Ransomware use
Unknown

CISA records ransomware use only for campaigns it has confirmed, so “Unknown” means unrecorded, not ruled out. The deadline binds US federal agencies; for everyone else it is a reference date.

Public exploits, PoCs and detection templates

Public code that demonstrates or tests the flaw raises the odds of mass exploitation — and Nuclei templates help find vulnerable assets in your environment.

Detection templates (Nuclei)
Proofs of concept on GitHub

Warning: public PoCs are sometimes disguised malware. Use them only for authorized testing in an isolated environment. This portal does not host exploit code — it only points to the sources.

EPSS over time FIRST

Oct 12, 2026 → Oct 14, 2026 · 3 reading(s) · max 99.59%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
  • Review authentication logs: logins without MFA, anomalous sessions and recently created accounts.
  • Hunt retroactively in logs from before Aug 21, 2024 (KEV listing): exploitation may have started earlier.
web/proxy/WAF logsnetwork IDS/IPSauthentication logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Affected products added · dahuasecurity/ipc-hum7xxx firmware, dahuasecurity/ipc-hx3xxx firmware, dahuasecurity/ipc-hx5xxx firmware, dahuasecurity/
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 9.8
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Added to CISA KEV (detected)
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • Record created in this database
    Oct 13, 2026 · CISA Known Exploited Vulnerabilities
  • 2024
  • Added to CISA KEV catalog
    Aug 20, 2024 · CISA
  • 2021
  • CVE published
    Sep 15, 2021 · dahua

Source activity

Repeated readings are counted rather than listed.

  • 2× References added · Oct 13, 2026 – Oct 13, 2026
  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

6 on the record

Elsewhere on this site

Dahuasecurity
every CVE for this vendor
2024-08
what else CISA listed that month
Authentication
same class
CWE-287
other pages naming this weakness

Related CVEs (same products)

  • Critical CVE-2021-33044 Dahua IP Camera Authentication Bypass Vulnerability KEV Sep 15, 2021

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No fixed version, patch or mitigation documented.
  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2021-33045 is "Dahua IP Camera Authentication Bypass Vulnerability", rated Critical. It affects Ipc-hum7xxx Firmware (Dahuasecurity); versions are in the scope table. It is in CISA KEV: there is evidence of real-world exploitation. CVSS 9.8 describes technical severity. EPSS 99.59% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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