CVE-2021-20034

Exp

An improper access control vulnerability in SMA100 allows a remote unauthenticated attacker to bypass the path traversal checks and delete an arbitrary file potentially resulting in a reboot to factory default settings.

Published: 2021-09-27 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2021-20034 is rated High Exploit Risk (85.8/100): CVSS Critical severity, with high exploitation likelihood (EPSS 80.70%, 100th percentile). 2 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

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

Public exploit references (Exploit-DB) for CVE-2021-20034

EDB-ID Source Kind Published Link
50430 exploit_db edb 2021-10-20 Exploit-DB ↗
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2021-20034

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 2026-06-23 81.14% 80.70% -0.44%
2 2026-06-15 5.44% 81.14% +75.70%
3 2026-05-26 — 5.44% —

Full EPSS history (38 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-20034

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
9.1 3.1 CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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:N)
Doesn’t really leak secrets in a meaningful 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 5.2 [email protected]
6.4 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/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:N)
No confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 4.9 [email protected]

Weakness enumeration for CVE-2021-20034

Affected software / configurations for CVE-2021-20034

Vendor Product Version Raw CPE
sonicwall sma_200_firmware <= 9.0.0.10-28sv cpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma_200_firmware >= 10.2.0.0, <= 10.2.0.7-34sv cpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma_200_firmware >= 10.2.1.0, <= 10.2.1.0-17sv cpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma_210_firmware <= 9.0.0.10-28sv cpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma_210_firmware >= 10.2.0.0, <= 10.2.0.7-34sv cpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma_210_firmware >= 10.2.1.0, <= 10.2.1.0-17sv cpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma_400_firmware <= 9.0.0.10-28sv cpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma_400_firmware >= 10.2.0.0, <= 10.2.0.7-34sv cpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma_400_firmware >= 10.2.1.0, <= 10.2.1.0-17sv cpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma_410_firmware <= 9.0.0.10-28sv cpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma_410_firmware >= 10.2.0.0, <= 10.2.0.7-34sv cpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma_410_firmware >= 10.2.1.0, <= 10.2.1.0-17sv cpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma_500v <= 9.0.0.10-28sv cpe:2.3:a:sonicwall:sma_500v:*:*:*:*:*:*:*:*
sonicwall sma_500v >= 10.2.0.0, <= 10.2.0.7-34sv cpe:2.3:a:sonicwall:sma_500v:*:*:*:*:*:*:*:*
sonicwall sma_500v >= 10.2.1.0, <= 10.2.1.0-17sv cpe:2.3:a:sonicwall:sma_500v:*:*:*:*:*:*:*:*

References for CVE-2021-20034

cvelogic Threat Intelligence