Vulnerability record

CVE-2021-20023

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Full record read. Reported values and explicit gaps below come from the tracked record. Tracker snapshot: Aug 8, 2026.

What it is

Reported

SonicWall Email Security contains a path traversal vulnerability that allows a post-authenticated attacker to read files on the remote host. This vulnerability has known usage in a SonicWall Email Security exploit chain along with CVE-2021-20021 and CVE-2021-20022 to achieve privilege escalation. Source description excerpt; complete tracked detail loads below.

NVD published: Apr 20, 2021 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What is affected

Reported

SonicWall — SonicWall Email Security. Product-level identification only; no affected-version conclusion is available from this field.

NVD published: Apr 20, 2021 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Urgency and basis

Reported

Act now · 557.5

Tracker decision tier from the evidence detailed below · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Exploitation evidence

Reported

Active exploitation · CISA KEV · VulnCheck KEV · ENISA exploited-vulnerability catalog

Active since: Nov 3, 2021 · CISA KEV added: Nov 3, 2021 · VulnCheck KEV added: Apr 20, 2021 · ENISA added: Nov 3, 2021 · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

What to do

Reported

Apply updates per vendor instructions.

Source remediation ↗

Tracked source remediation field · Source record updated: Aug 8, 2026 · Tracker snapshot: Aug 8, 2026

Evidence detail

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