CVE-2026-31933: Suricata stream: quadratic complexity in stream inspection

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.4% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-02 · updated 2026-10-26
Weakness: CWE-407

Description

Suricata is a network IDS, IPS and NSM engine. Prior to versions 7.0.15 and 8.0.4, specially crafted traffic can cause Suricata to slow down, affecting performance in IDS mode. This issue has been patched in versions 7.0.15 and 8.0.4.

Affected products

OISF suricata: before 7.0.15; from 8.0.0 before 8.0.4 — fixed in 7.0.15, 8.0.4

How to fix

Upgrade to a fixed version: OISF suricata 7.0.15, 8.0.4. Check the vendor advisory for mitigations.

References

https://github.com/OISF/suricata/security/advisories/GHSA-hvp5-gpr6-j4gp
https://redmine.openinfosecfoundation.org/issues/8272

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