CVE-2021-38530

Certain NETGEAR devices are affected by command injection by an unauthenticated attacker. This affects RBK40 before 2.5.1.16, RBR40 before 2.5.1.16, RBS40 before 2.5.1.16, RBK20 before 2.5.1.16, RBR20 before 2.5.1.16, RBS20 before 2.5.1.16, RBK50 before 2.5.1.16, RBR50 before 2.5.1.16, RBS50 before 2.5.1.16, and RBS50Y before 2.6.1.40.

Published: 2021-08-10 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-38530 is rated High Risk (67.1/100): CVSS Critical severity, with medium exploitation likelihood (EPSS 2.22%). 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-2021-38530

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 1.66% 2.22% +0.56%
2 2025-11-21 3.30% 1.66% -1.64%
3 2025-11-18 — 3.30% —

Full EPSS history (16 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-38530

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.6 3.1 CRITICAL
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
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:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
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.
 2.8 6.0 [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 [email protected]
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-2021-38530

Affected software / configurations for CVE-2021-38530

Vendor Product Version Raw CPE
netgear rbk40_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbk40_firmware:*:*:*:*:*:*:*:*
netgear rbr40_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbr40_firmware:*:*:*:*:*:*:*:*
netgear rbs40_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbs40_firmware:*:*:*:*:*:*:*:*
netgear rbk20_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbk20_firmware:*:*:*:*:*:*:*:*
netgear rbr20_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbr20_firmware:*:*:*:*:*:*:*:*
netgear rbs20_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbs20_firmware:*:*:*:*:*:*:*:*
netgear rbk50_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbk50_firmware:*:*:*:*:*:*:*:*
netgear rbr50_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbr50_firmware:*:*:*:*:*:*:*:*
netgear rbs50_firmware < 2.5.1.16 cpe:2.3:o:netgear:rbs50_firmware:*:*:*:*:*:*:*:*
netgear rbs50y_firmware < 2.6.1.40 cpe:2.3:o:netgear:rbs50y_firmware:*:*:*:*:*:*:*:*

References for CVE-2021-38530

cvelogic Threat Intelligence