# CVE-2026-44392: Six Apart Movable Type missing authorization in upgrade process

Source: https://junglewise.ai/threats/cve-2026-44392-six-apart-movable-type-missing-authorization-in-upgrade-process  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-05-20. Updated: 2026-05-20  
License: CC BY 4.0 with a link back

CVE-2026-44392 · Severity: medium · CVSS 4.3 · Published 2026-05-20

Movable Type, a popular content management system, contains a security flaw that allows users with low-level access to perform administrative update tasks. Specifically, when the software or its plugins require an update, a user without administrator privileges can trigger the upgrade process. This could lead to unauthorized changes to the system configuration or unintended service modifications.

Technologies: [Six Apart Ltd. Movable Type Premium](https://junglewise.ai/threats/technologies/movable-type-premium). Vendors: [Six Apart Ltd.](https://junglewise.ai/threats/vendors/six-apart-ltd).

## Quick answers

**Is CVE-2026-44392 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-44392 being exploited in the wild.

**How severe is CVE-2026-44392?** Medium severity, with a CVSS score of 4.3, published 20 May 2026.

**Which products and versions are affected?** Six Apart Ltd. Movable Type Premium 9.1.0 and earlier, 9.0.6 and earlier, 2.14 and earlier, 1.0 to 1.68.

**Is there a fix for CVE-2026-44392?** A patch was published on 2026-05-20: Fixed versions 9.2.0, 9.0.8, 8.8.4, and 8.0.11 released. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-44392 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-44392?** Check whether you run Six Apart Ltd. Movable Type Premium 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

A missing authorization vulnerability (CWE-862) exists in Movable Type and Movable Type Premium. The flaw resides in the upgrade logic; when the core product or installed plugins are pending an upgrade, the system fails to properly verify administrative privileges before allowing a signed-in user to initiate the update processing. An authenticated attacker with low-level (non-admin) privileges can exploit this to execute unintended update tasks. The vendor has addressed this by introducing the 'RequireUpgradePermission' environment variable to enforce proper authorization checks. Patches are available in versions 9.2.0, 9.0.8, 8.8.4, and 8.0.11.

## Affected products

- Six Apart Ltd. Movable Type 9.1.0 and earlier, 9.0.6 and earlier, 8.8.2 and earlier, 8.0.9 and earlier, 7 series, 6 series, 5 series
- Six Apart Ltd. Movable Type Premium 9.1.0 and earlier, 9.0.6 and earlier, 2.14 and earlier, 1.0 to 1.68

## Timeline

- 2026-05-20: disclosed: Vulnerability disclosed by JPCERT/CC and Six Apart Ltd.
- 2026-05-20: patched: Fixed versions 9.2.0, 9.0.8, 8.8.4, and 8.0.11 released.

## References

- [https://jvn.jp/en/jp/JVN66473735/](https://jvn.jp/en/jp/JVN66473735/)
- [https://movabletype.org/news/2026/05/mt-908-released.html](https://movabletype.org/news/2026/05/mt-908-released.html)
- [https://www.sixapart.jp/movabletype/news/2026/05/20-1100.html](https://www.sixapart.jp/movabletype/news/2026/05/20-1100.html)

## Related threats

- [Movable Type code injection in Dynamic Publishing](https://junglewise.ai/threats/cve-2026-117687-movable-type-provided-by-six-apart-ltd-contains-a-code-injection)
- [Six Apart Movable Type code injection in Listing Framework](https://junglewise.ai/threats/cve-2026-25776-six-apart-movable-type-code-injection-in-listing-framework)