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Exploited vulnerability

CVE-2021-20023

TLP:CLEAR

SonicWall Email Security Path Traversal Vulnerability

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.

Facts

  • Vendor: SonicWall
  • Product: SonicWall Email Security
  • CVSS: 4.9
  • EPSS (probability of exploitation within 30 days): 51.7 %
  • On CISA's Known Exploited Vulnerabilities list since: 3 November 2021
  • First known exploitation: 3 November 2021
  • Used in ransomware campaigns (per CISA): Yes
  • CISA's deadline for US federal agencies: 17 November 2021
  • Weakness: CWE-22
  • First seen by Risk Letters: 3 November 2021

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Data: NVD (public domain), CISA KEV, FIRST EPSS, MITRE ATT&CK, AlienVault OTX. NVD

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