Resource exhaustion in Suricata - CVE-2026-63448
Published: July 22, 2026
Vulnerability identifier: #VU139039
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-63448
CWE-ID: CWE-400
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: Open Information Security Foundation
Affected software:
Suricata
Suricata
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to uncontrolled resource consumption in the SMB parser when processing sustained one-directional SMB flows. A remote attacker can send traffic that creates many force-completed SMB transactions to cause a denial of service.
The issue occurs when only one direction of the SMB flow contains payload, allowing per-flow transaction state to grow without bound and causing cleanup to repeatedly rescan an increasing transaction list.
How to mitigate CVE-2026-63448
Install security update from vendor's website.