CVE-2021-20042 json
An unauthenticated remote attacker can use SMA 100 as an unintended proxy or intermediary undetectable proxy to bypass firewall rules.
published 4y ago modified 4mo ago also EUVD-2021-7505
- cvss
- 9.8
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 3.7%
- EPSS 3.7% chance of exploitation in 30 days, percentile 89%
- public exploits
- 0
- none known
Summary
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.
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3.68% chance of exploitation in the next 30 days, higher than 89% of all scored CVEs (FIRST EPSS, 2026-11-09).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- SonicWall SonicWall SMA100
Classification
- Weakness
-
- CWE-441 Unintended Proxy or Intermediary
References
-
psirt.global.sonicwall.com
/vuln-detail/SNWLID-2021-0026
vendor-advisory
Sources
- CVE List CVE-2021-20042
- NVD CVE-2021-20042
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