CVE-2026-63446

Suricata app-layer: passed flows can retain transactions, causing resource exhaustion

Published Sep 18, 2026 CVSS 3.1 · 7.5 High EPSS < 1% KEV · Not listed
Description
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.

Remediation

No solution or workaround provided in the CVE record

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
CPEs cpe:2.3:a:oisf:suricata:*:*:*:*:*:*:*:*
Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}

Type Values Removed Values Added
First Time appeared Oisf
Oisf suricata
Vendors & Products Oisf
Oisf suricata
Type Values Removed Values Added
Description 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.
Title Suricata app-layer: passed flows can retain transactions, causing resource exhaustion
Weaknesses CWE-401
CWE-407
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Weaknesses

Sources

Status
PUBLISHED
Assigner
GitHub_M
Published
Updated
Sep 21, 2026, 4:20 PM
Reserved
Jul 16, 2026, 7:35 PM
Status
Analyzed
Published
Sep 18, 2026, 9:17 PM
Modified
Sep 28, 2026, 6:34 PM