CVE-2021-20042

highpriority · track · 40EPSS 0.037 · 90 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

3.68% (90th) EPSS

CVSS 7.5 · high

Is it mine?

19 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-24

An unauthenticated remote attacker can use SMA 100 as an unintended proxy or intermediary undetectable proxy to bypass firewall rules. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.5–9.8

v2.07.5highAV:N/AC:L/Au:N/C:P/I:P/A:Pprimary · NVD / NIST USexploitability 10 · impact 6.4

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-441US

affected products (19)

Products and version ranges known to be affected.

SonicWall SonicWall SMA100≤ 10.2.0.8-37sv and earlierenisa_euvdEU
SonicWall SonicWall SMA100≤ 9.0.0.11-31sv and earlierenisa_euvdEU
SonicWall SonicWall SMA100≤ 10.2.1.1-19sv and earlierenisa_euvdEU
SonicWall SonicWall SMA100≤ 10.2.1.2-24sv and earlierenisa_euvdEU
sonicwall sma 200 firmware= 10.2.0.8-37svnvdUScpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma 200 firmware= 10.2.1.1-19svnvdUScpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma 200 firmware= 9.0.0.11-31svnvdUScpe:2.3:o:sonicwall:sma_200_firmware:*:*:*:*:*:*:*:*
sonicwall sma 210 firmware= 10.2.0.8-37svnvdUScpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma 210 firmware= 10.2.1.1-19svnvdUScpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma 210 firmware= 9.0.0.11-31svnvdUScpe:2.3:o:sonicwall:sma_210_firmware:*:*:*:*:*:*:*:*
sonicwall sma 400 firmware= 10.2.0.8-37svnvdUScpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma 400 firmware= 10.2.1.1-19svnvdUScpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma 400 firmware= 9.0.0.11-31svnvdUScpe:2.3:o:sonicwall:sma_400_firmware:*:*:*:*:*:*:*:*
sonicwall sma 410 firmware= 10.2.0.8-37svnvdUScpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma 410 firmware= 10.2.1.1-19svnvdUScpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma 410 firmware= 9.0.0.11-31svnvdUScpe:2.3:o:sonicwall:sma_410_firmware:*:*:*:*:*:*:*:*
sonicwall sma 500v firmware= 10.2.0.8-37svnvdUScpe:2.3:o:sonicwall:sma_500v_firmware:*:*:*:*:*:*:*:*
sonicwall sma 500v firmware= 10.2.1.1-19svnvdUScpe:2.3:o:sonicwall:sma_500v_firmware:*:*:*:*:*:*:*:*
sonicwall sma 500v firmware= 9.0.0.11-31svnvdUScpe:2.3:o:sonicwall:sma_500v_firmware:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2021-12-08modified 2026-06-17

references (5)

External citations — patches, advisories, analysis.

scry

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