What’s Vulnerable › Vulnerabilities

CVE-2021-37592

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-11-19 · updated 2026-06-17
• Weakness: CWE-787

Description

Suricata before 5.0.8 and 6.x before 6.0.4 allows TCP evasion via a client with a crafted TCP/IP stack that can send a certain sequence of segments.

Affected products

• OISF suricata: before 5.0.8; from 6.0.0 before 6.0.4 — fixed in 5.0.8, 6.0.4

How to fix

Upgrade to a fixed version: OISF suricata 5.0.8, 6.0.4. Check the vendor advisory for mitigations.

References

• https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942
• https://github.com/OISF/suricata/releases
• https://redmine.openinfosecfoundation.org/issues/4569
• https://forum.suricata.io/t/suricata-6-0-4-and-5-0-8-released/1942
• https://github.com/OISF/suricata/releases
• https://redmine.openinfosecfoundation.org/issues/4569

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