CVE-2026-55439: Halo is an open source website building tool. Prior to 2.24.3, a path traversal vulnerability in the backup download endpoint allows authenticated adm...

Description

Halo is an open source website building tool. Prior to 2.24.3, a path traversal vulnerability in the backup download endpoint allows authenticated administrators to read arbitrary files from the server filesystem. The backup download endpoint (GET /apis/console.api.migration.halo.run/v1alpha1/backups/{name}/files/{filename}) in MigrationServiceImpl.download() resolves the backup filename via Path.resolve() without validating that the resolved path stays within the designated backups directory. Also, the Backup creation endpoint (POST /apis/migration.halo.run/v1alpha1/backups) does not sanitize the status fields during creation This vulnerability is fixed in 2.24.3.

Metrics

CVSS 3.1

5.5/10

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

EPSS Probability

0.34%

25.6th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

References

Timeline

Published: Jun 25, 2026
Last Modified: Jun 25, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2026-55439?

Halo is an open source website building tool. Prior to 2.24.3, a path traversal vulnerability in the backup download endpoint allows authenticated administrators to read arbitrary files from the server filesystem. The backup download endpoint (GET /apis/console.api.migration.halo.run/v1alpha1/backups/{name}/files/{filename}) in MigrationServiceImpl.download() resolves the backup filename via Path.resolve() without validating that the resolved path stays within the designated backups directory. Also, the Backup creation endpoint (POST /apis/migration.halo.run/v1alpha1/backups) does not sanitize the status fields during creation This vulnerability is fixed in 2.24.3.

How severe is CVE-2026-55439?

CVE-2026-55439 has a CVSS score of 5.5/10 (MEDIUM severity). The EPSS model estimates a 0.34% probability of exploitation in the next 30 days.

How do I fix CVE-2026-55439?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.