CVE-2026-63446: Oisf Suricata

High severity, CVSS 7.5. EPSS: 0.7% chance of exploitation in the next 30 days.

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.0 until 8.0.6, AppLayerParserSetTransactionInspectId() in src/app-layer-parser.c uses an inverted guard and marks only already-inspected transactions as inspected. On flows passed by a pass rule or pass-the-flow exception policy, detection is skipped, so completed transactions remain unmarked, are never freed, and are repeatedly rescanned. The per-flow list can grow without bound with quadratic cleanup cost, causing CPU and memory exhaustion. This issue is fixed in version 8.0.6.

Affected products

• Oisf Suricata: from 8.0.0, before 8.0.6 (fixed in 8.0.6)

Published 2026-09-18. Last modified 2026-09-28.