Is CVE-2026-55439 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-55439 being exploited in the wild.

How severe is CVE-2026-55439?

Medium severity, with a CVSS score of 5.5, published 25 June 2026.

Is there a fix for CVE-2026-55439?

A patch was published on 2026-06-25: Fix released in version 2.24.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-55439 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-55439?

Check whether you run Halo 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-2026-55439: Halo path traversal in backup download endpoint

CVE-2026-55439 · Severity: medium · CVSS 5.5 · Published 2026-06-25

Halo, an open-source website building tool, contains a security flaw in its backup management system. An authorized administrator could exploit this to bypass security restrictions and read sensitive files directly from the server's filesystem. This could lead to the exposure of configuration files, credentials, or other private data, though it does not allow for the modification of files or full system takeover.

Technologies: Halo. Vendors: Halo.

Quick answers

Is CVE-2026-55439 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-55439 being exploited in the wild.
How severe is CVE-2026-55439?: Medium severity, with a CVSS score of 5.5, published 25 June 2026.
Which products and versions are affected?: Halo < 2.24.3.
Is there a fix for CVE-2026-55439?: A patch was published on 2026-06-25: Fix released in version 2.24.3 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-55439 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-55439?: Check whether you run Halo 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 path traversal vulnerability (CWE-22) exists in the Halo backup download endpoint `GET /apis/console.api.migration.halo.run/v1alpha1/backups/{name}/files/{filename}`. The `MigrationServiceImpl.download()` method utilizes `Path.resolve()` on the filename without validating that the resulting path remains within the intended backups directory. An attacker with administrative privileges can first create a Backup resource via a POST request with a manipulated `status.filename` (e.g., `../../../etc/passwd`) and then trigger the download endpoint to retrieve arbitrary files. While Halo contains a `checkDirectoryTraversal()` utility, it was omitted in the download implementation. The issue is resolved in version 2.24.3.

Affected products

halo-dev Halo < 2.24.3

Timeline

2026-06-17: advisory: GitHub Security Advisory published
2026-06-25: disclosed: NVD publication date
2026-06-25: patched: Fix released in version 2.24.3

References

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