CVE-2021-33045

Exp

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: 2021-09-15 Last update: 2026-01-13 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-33045 is rated Critical Active Threat (100/100): CVSS Critical severity, with high exploitation likelihood (EPSS 99.56%, 100th percentile). Core evidence: CISA KEV confirms active exploitation (added 2024-08-21) affecting Dahua / IP Camera Firmware. an authentication bypass (CWE-287) Unauthenticated remote administrative access may be possible. EPSS rose +5.38% over the last day, indicating growing attacker interest. Mandatory action: The CISA remediation deadline has passed—treat as an emergency patch priority.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

CISA KEV Record for CVE-2021-33045

Name: Dahua IP Camera Authentication Bypass Vulnerability · CISA KEV detail

Exploit added: 2024-08-21

Action due: 2024-09-11

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

Public exploit references (Exploit-DB) for CVE-2021-33045

EDB-ID Source Kind Published Link
nvd_ref exploit_tag Exploit-DB ↗
nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-33045

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 94.17% 99.56% +5.38%
2 2026-05-01 94.14% 94.17% +0.03%
3 2026-03-28 94.14%

Full EPSS history (29 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-33045

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 [email protected]
9.8 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
3.9 5.9 134c704f-9b21-4f2e-91b3-4a467353bcc0
10.0 2.0 HIGH
AV:N/AC:L/Au:N/C:C/I:C/A:C Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:C)
Complete confidentiality impact.
Integrity impact (I:C)
Complete integrity impact.
Availability impact (A:C)
Complete availability impact.
10.0 10.0 [email protected]

Weakness enumeration for CVE-2021-33045

Affected software / configurations for CVE-2021-33045

Vendor Product Version Raw CPE
dahuasecurity ipc-hum7xxx_firmware < 2.820.0000000.5.r.210705 cpe:2.3:o:dahuasecurity:ipc-hum7xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hx3xxx_firmware < 2.800.0000000.29.r.210630 cpe:2.3:o:dahuasecurity:ipc-hx3xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hx5xxx_firmware < 2.820.0000000.5.r.210705 cpe:2.3:o:dahuasecurity:ipc-hx5xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity nvr-1xxx_firmware < 4.001.0000005.1.r.210709 cpe:2.3:o:dahuasecurity:nvr-1xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity nvr-2xxx_firmware < 4.001.0000000.1.r.210710 cpe:2.3:o:dahuasecurity:nvr-2xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity nvr-4xxx_firmware < 4.001.0000005.1.r.210713 cpe:2.3:o:dahuasecurity:nvr-4xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity nvr-5xxx_firmware < 4.001.0000000.0.r.210710 cpe:2.3:o:dahuasecurity:nvr-5xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity nvr-6xx_firmware < 4.001.0000001.1.r.210716 cpe:2.3:o:dahuasecurity:nvr-6xx_firmware:*:*:*:*:*:*:*:*
dahuasecurity vth-542xh_firmware < 4.500.0000002.0.r.210715 cpe:2.3:o:dahuasecurity:vth-542xh_firmware:*:*:*:*:*:*:*:*
dahuasecurity vto-65xxx_firmware < 4.300.0000004.0.r.210715 cpe:2.3:o:dahuasecurity:vto-65xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity vto-75x95x_firmware < 4.300.0000003.0.r.210714 cpe:2.3:o:dahuasecurity:vto-75x95x_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-4x04_firmware cpe:2.3:o:dahuasecurity:xvr-4x04_firmware:-:*:*:*:*:*:*:*
dahuasecurity xvr-4x08_firmware < 4.001.0000001.1.r.210709 cpe:2.3:o:dahuasecurity:xvr-4x08_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-4x04_firmware < 4.001.0000001.1.r.210709 cpe:2.3:o:dahuasecurity:xvr-4x04_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-5x04_firmware < 4.001.0000003.1.r.210710 cpe:2.3:o:dahuasecurity:xvr-5x04_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-5x08_firmware < 4.001.0000003.1.r.210710 cpe:2.3:o:dahuasecurity:xvr-5x08_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-5x16_firmware < 4.001.0000003.1.r.210710 cpe:2.3:o:dahuasecurity:xvr-5x16_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-7x16_firmware < 4.001.0000003.1.r.210710 cpe:2.3:o:dahuasecurity:xvr-7x16_firmware:*:*:*:*:*:*:*:*
dahuasecurity xvr-7x32_firmware < 4.001.0000003.1.r.210710 cpe:2.3:o:dahuasecurity:xvr-7x32_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-33045

cvelogic Threat Intelligence