CVE-2020-9502

Some Dahua products with Build time before December 2019 have Session ID predictable vulnerabilities. During normal user access, an attacker can use the predicted Session ID to construct a data packet to attack the device.

Published: 2020-05-13 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-9502 is rated High Risk (66.4/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 1.72%). EPSS rose +1.11% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

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

Exploit prediction scoring system (EPSS) score for CVE-2020-9502

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 0.60% 1.72% +1.11%
2 2025-11-21 0.50% 0.60% +0.10%
3 2025-11-18 — 0.50% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-9502

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]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/A:P 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:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2020-9502

Affected software / configurations for CVE-2020-9502

Vendor Product Version Raw CPE
dahuasecurity sd6al_firmware < 2019-12 cpe:2.3:o:dahuasecurity:sd6al_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd5a_firmware < 2019-12 cpe:2.3:o:dahuasecurity:sd5a_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd1a_firmware < 2019-12 cpe:2.3:o:dahuasecurity:sd1a_firmware:*:*:*:*:*:*:*:*
dahuasecurity ptz1a_firmware < 2019-12 cpe:2.3:o:dahuasecurity:ptz1a_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd50_firmware < 2019-12 cpe:2.3:o:dahuasecurity:sd50_firmware:*:*:*:*:*:*:*:*
dahuasecurity sd52c_firmware < 2019-12 cpe:2.3:o:dahuasecurity:sd52c_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hx5842h_firmware < 2019-12 cpe:2.3:o:dahuasecurity:ipc-hx5842h_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hx7842h_firmware < 2019-12 cpe:2.3:o:dahuasecurity:ipc-hx7842h_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hx2xxx_firmware < 2019-12 cpe:2.3:o:dahuasecurity:ipc-hx2xxx_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hxxx5x4x_firmware < 2019-12 cpe:2.3:o:dahuasecurity:ipc-hxxx5x4x_firmware:*:*:*:*:*:*:*:*
dahuasecurity n42b1p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n42b1p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n42b2p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n42b2p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n42b3p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n42b3p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n52a4p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n52a4p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n54a4p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n54a4p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n52b2p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n52b2p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n52b5p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n52b5p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n52b3p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n52b3p_firmware:*:*:*:*:*:*:*:*
dahuasecurity n54b2p_firmware < 2019-12 cpe:2.3:o:dahuasecurity:n54b2p_firmware:*:*:*:*:*:*:*:*
dahuasecurity ipc-hdbw1320e-w_firmware < 2019-12 cpe:2.3:o:dahuasecurity:ipc-hdbw1320e-w_firmware:*:*:*:*:*:*:*:*

References for CVE-2020-9502

cvelogic Threat Intelligence