CVE-2021-33044

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]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-33044 is rated Critical Active Threat (100/100): CVSS Critical severity, with high exploitation likelihood (EPSS 99.87%, 100th percentile). 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 +5.60% over the last day, indicating growing attacker interest. 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-2021-33044

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-2021-33044

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-2021-33044

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 94.27% 99.87% +5.60%
2 2026-05-18 94.25% 94.27% +0.02%
3 2026-03-25 — 94.25% —

Full EPSS history (35 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-33044

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-2021-33044

Affected software / configurations for CVE-2021-33044

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 < 2.820.0000000.18.r.210705 cpe:2.3:o:dahuasecurity:ipc-hx5xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd1a1_firmware < 2.812.0000007.0.r.210706 cpe:2.3:o:dahuasecurity:sd1a1_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd22_firmware < 2.812.0000007.0.r.210706 cpe:2.3:o:dahuasecurity:sd22_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd49_firmware < 2.812.0000007.0.r.210706 cpe:2.3:o:dahuasecurity:sd49_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd50_firmware < 2.812.0000007.0.r.210706 cpe:2.3:o:dahuasecurity:sd50_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd52c_firmware < 2.812.0000007.0.r.210706 cpe:2.3:o:dahuasecurity:sd52c_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd6al_firmware < 2.812.0000007.0.r.210706 cpe:2.3:o:dahuasecurity:sd6al_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-bf1241_firmware < 2.630.0000000.6.r.210707 cpe:2.3:o:dahuasecurity:tpc-bf1241_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-bf2221_firmware < 2.630.0000000.10.r.210707 cpe:2.3:o:dahuasecurity:tpc-bf2221_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-bf5x01_firmware < 2.630.0000000.12.r.210707 cpe:2.3:o:dahuasecurity:tpc-bf5x01_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-pt8x21b_firmware < 2.630.0000000.10.r.210701 cpe:2.3:o:dahuasecurity:tpc-pt8x21b_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-sd2221_firmware <= 2.630.0000000.7.r.210707 cpe:2.3:o:dahuasecurity:tpc-sd2221_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-sd8x21_firmware < 2.630.0000000.9.r.210706 cpe:2.3:o:dahuasecurity:tpc-sd8x21_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 vth-542xh_firmware < 4.500.0000002.0.r.210715 cpe:2.3:o:dahuasecurity:vth-542xh_firmware:*:*:*:*:*:*:*:*
dahuasecurity tpc-bf5x21_firmware < 2.630.0000000.8.r.210630 cpe:2.3:o:dahuasecurity:tpc-bf5x21_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-33044

cvelogic Threat Intelligence