Is CVE-2026-63448 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-63448 being exploited in the wild.

How severe is CVE-2026-63448?

Medium severity, with a CVSS score of 5.9, published 18 September 2026.

Which products and versions are affected?

OISF Suricata prior to 7.0.17 and 8.0.6.

Is there a fix for CVE-2026-63448?

A patch was published on 2026-07-01: Fix committed to main branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-63448 attacked?

It is attacked over the network, in a hosted service.

Am I affected by CVE-2026-63448?

Check whether you run OISF Suricata at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-63448: Suricata SMB parser unbounded transaction accumulation DoS

CVE-2026-63448 · Severity: medium · CVSS 5.9 · Published 2026-09-18

Suricata is a network security monitoring and intrusion detection system that inspects network traffic for threats. A flaw in its SMB protocol parser allows an attacker to send sustained one-directional SMB traffic that causes unbounded accumulation of transaction state in memory and CPU, exhausting server resources and disrupting network monitoring capability.

Technologies: OISF Suricata. Vendors: OISF.

Quick answers

Is CVE-2026-63448 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-63448 being exploited in the wild.
How severe is CVE-2026-63448?: Medium severity, with a CVSS score of 5.9, published 18 September 2026.
Which products and versions are affected?: OISF Suricata prior to 7.0.17 and 8.0.6.
Is there a fix for CVE-2026-63448?: A patch was published on 2026-07-01: Fix committed to main branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-63448 attacked?: It is attacked over the network, in a hosted service.
Am I affected by CVE-2026-63448?: Check whether you run OISF Suricata at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The SMB parser in Suricata's Rust codebase fails to properly enforce the SMB_MAX_TX transaction limit on asymmetric flows where payload is observed in only one direction, including async-oneside flows. The transaction cleanup mechanism waits for inspection in the unseen direction, allowing transactions to accumulate without bound. An attacker sending sustained one-directional SMB traffic can exhaust CPU and memory resources on the monitored system.

Affected products

OISF Suricata prior to 7.0.17 and 8.0.6

Timeline

2026-09-18: disclosed: CVE-2026-63448 published
2026-07-01: patched: Fix committed to main branch
2026-07-07: patched: Fix available in versions 7.0.17 and 8.0.6

References

This page as Markdown. Free to reuse under CC BY 4.0 with a link back.