---
title: "CVE-2026-63448\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2026-63448?format=md
keywords: index, follow
---

# CVE-2026-63448

Publication date 21 September 2026

Last updated 21 September 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**5.9 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2026-63448?format=md#impact-score)

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## Description

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.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| suricata | 26.04 LTS resolute | Needs evaluation |
| 24.04 LTS noble | Needs evaluation |
| 22.04 LTS jammy | Needs evaluation |
| 18.04 LTS bionic | Needs evaluation |
| 16.04 LTS xenial | Needs evaluation |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.9 · Medium

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | High |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | None |
  | Integrity impact | None |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.9 · Medium |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2026-63448)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2026-63448)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2026-63448)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2026-63448)

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2026-63448>
* <https://github.com/OISF/suricata/security/advisories/GHSA-hvvj-c8xx-9g35>
* <https://github.com/OISF/suricata/commit/755d6c3061de4d7ba97f0ed31cdc17ab8cab4476>
* <https://github.com/OISF/suricata/commit/7ec9d72d28b9370712cf77a5b9d40d6b5db27cb4>
* <https://github.com/OISF/suricata/commit/88adab8bd3d62912941647ab65032d5ec75c893a>
* <https://github.com/OISF/suricata/commit/9a54a043516e644bb7b9d34117a91977f950a281>
* <https://github.com/OISF/suricata/commit/bc39274a638d1cca2391cfa4891c8b6c255ff9ce>
* <https://github.com/OISF/suricata/commit/c8f68b0e4f9e721dca1c9ed6e08597c6964c7ac3>
* <https://github.com/OISF/suricata/releases/tag/suricata-7.0.17>
* <https://github.com/OISF/suricata/releases/tag/suricata-8.0.6>
* <https://redmine.openinfosecfoundation.org/issues/8629>