Resource exhaustion in Oisf Suricata

CVE-2026-63448

Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. Prior to 7.0.17 and 8.0.6, the SMB parser can retain force-completed transactions on flows where Suricata sees payload in only one direction, including async-oneside flows, because cleanup waits for inspection in the unseen direction. The transaction creation paths in rust/src/smb can exceed the intended SMB_MAX_TX bound, and cleanup repeatedly scans the growing list. Sustained one-directional SMB traffic can therefore cause unbounded per-flow state and CPU and memory exhaustion. This issue is fixed in versions 8.0.6 and 7.0.17.

Vulnerability class: DoS (Denial of Service)

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-63448?
CVE-2026-63448 is a medium-severity vulnerability in Oisf Suricata, classified under Uncontrolled Resource Consumption. CVSS score: 5.9/10. Published 2026-09-18.
How severe is CVE-2026-63448?
Medium severity. CVSS v3 base score is 5.9 out of 10.