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Fencer Intel
medium 6.1

CVE-2021-20031 json

A Host Header Redirection vulnerability in SonicOS potentially allows a remote attacker to redirect firewall management users to arbitrary…

published 5y ago modified 11h ago also EUVD-2021-7494

cvss
6.1
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
13.0%
EPSS 13.0% chance of exploitation in 30 days, percentile 96%
public exploits
1
Exploit-DB, plus a Nuclei check

Summary

A Host Header Redirection vulnerability in SonicOS potentially allows a remote attacker to redirect firewall management users to arbitrary web domains.

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Timeline

  1. Published
  2. First public exploit (EDB-50414)

Exploit prediction

12.98% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • EDB-50414 Sonicwall SonicOS 7.0 - Host Header Injection webapps, 2021-10-13
  • Nuclei template SonicWall SonicOS 7.0 - Open Redirect nuclei detection template
  • packetstormsecurity.com http://packetstormsecurity.com/files/164502/Sonicwall-SonicOS-7.0-Host-Header-Injection.html referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD 2.0 5.8 AV:N/AC:M/Au:N/C:P/I:P/A:N

Affected products

  • SonicWall SonicOS

Classification

Weakness
  • CWE-601 URL Redirection to Untrusted Site

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.