CVE-2026-22263: Suricata http1: quadratic complexity in headers parsing over multiple packets

Severity: medium (CVSS 5.3 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: 2026-01-27 · updated 2026-06-17
Weakness: CWE-1050

Description

Suricata is a network IDS, IPS and NSM engine. Starting in version 8.0.0 and prior to version 8.0.3, inefficiency in http1 headers parsing can lead to slowdown over multiple packets. Version 8.0.3 patches the issue. No known workarounds are available.

Affected products

OISF suricata: from 8.0.0 before 8.0.3 — fixed in 8.0.3

How to fix

Upgrade to a fixed version: OISF suricata 8.0.3. Check the vendor advisory for mitigations.

References

https://github.com/OISF/suricata/commit/018a377f74e3eb2b042c6f783ad9043060923428
https://github.com/OISF/suricata/security/advisories/GHSA-rwc5-hxj6-hwx7
https://redmine.openinfosecfoundation.org/issues/8201

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