CASCACascade Atlas

Evidence dossier

CVE-2021-20038

CVE-2021-20038

78.7–99.5Priority evidence range
As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.

State
PUBLISHED
Published
Dec 8, 2021
Updated
Oct 21, 2025
Evidence coverage
72%
CISA KEVCatalog member

Apply updates per vendor instructions.

FIRST EPSS99.91%

2026-07-18 · v2026.06.15 · percentile 100.0%

Source stateConflict visible

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

CISA-ADPindependent enrichment
container

CISA ADP Vulnrichment

CVEderivative copy
container

CVE Program Container

sonicwalloriginal assertion
container

A Stack-based buffer overflow vulnerability in SMA100 Apache httpd server's mod_cgi module environment variables allows a remote unauthenticated attacker to potentially execute code as a 'nobody' user in the appliance. This vulnerability affected SMA 200, 210, 400, 410 and 500v appliances firmware 10.2.0.8-37sv, 10.2.1.1-19sv, 10.2.1.2-24sv and earlier versions.

CISA KEVoriginal assertion
observed_exploitation

SonicWall SMA 100 Appliances Stack-Based Buffer Overflow Vulnerability

FIRST EPSSoriginal assertion
model_probability

Probability 0.999120000000; percentile 0.999670000000

Applicability

Cited product scope

Trace impact →
SonicWallSonicWall SMA100
[{"status": "affected", "version": "10.2.0.8-37sv and earlier"}, {"status": "affected", "version": "10.2.1.1-19sv and earlier"}, {"status": "affected", "version": "10.2.1.2-24sv and earlier"}]unknown
Unknown vendorUnknown product
cpe:2.3:h:sonicwall:sma_200:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:sonicwall:sma_210:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:sonicwall:sma_400:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:sonicwall:sma_410:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:h:sonicwall:sma_500v:-:*:*:*:*:*:*:*constrained
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_200_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_200_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_200_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_210_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_400_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_410_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.0.8-37sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.1.1-19sv:*:*:*:*:*:*:*supported
Unknown vendorUnknown product
cpe:2.3:o:sonicwall:sma_500v_firmware:10.2.1.2-24sv:*:*:*:*:*:*:*supported

Assessments

CVSS by origin

9.8
nvd@nist.govCVSS 3.1 · role PrimaryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
7.5
nvd@nist.govCVSS 2.0 · role PrimaryAV:N/AC:L/Au:N/C:P/I:P/A:P
9.8
134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role SecondaryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
9.8
CISA-ADPCVSS 3.1 · role unknownCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Limitations and unknowns

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
  • NVD-carried upstream facts remain derivative and are not independent corroboration.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.