# CVE-2021-20023

SonicWall Email Security version 10.0.9.x contains a vulnerability that allows a post-authenticated attacker to read an arbitrary file on the remote host.

- Page: https://www.vulneraibility.com/cve/CVE-2021-20023
- CVSS: 4.9
- Known exploited: yes, in CISA KEV since 2021-11-03; CISA due date 2021-11-17; known ransomware use
- EPSS: 51.69% (percentile 99.0)
- CISA SSVC: exploitation active, automatable yes, technical impact total (assessed 2026-08-12)
- Weakness: CWE-22
- Published: 2021-04-20

## Affected versions

- SonicWall Email Security: affected 10.0.9 and earlier

A version outside these ranges is not a statement that it is unaffected.

## References

- [other] https://psirt.global.sonicwall.com/vuln-detail/SNWLID-2021-0010
- [other] https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2021-20023

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.