CVE-2026-63446

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

State
Published
Severity
7.5 High
Published
Sep 18, 2026
Updated
Sep 21, 2026
Reserved
Jul 16, 2026

Read the record on cve.org

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.

Scores

CVSSScoreVectorSource
3.17.5 HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HGitHub_M

Weaknesses

  • CWE-401 Missing Release of Memory after Effective Lifetime
  • CWE-407 Inefficient Algorithmic Complexity

Affected Products

ProductVersions
suricataOISF
  • >= 8.0.0, < 8.0.6Affected

References

Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.