The default cache strategy uses the basename of a remote schema as the name of the file in the cache, e.g. https://example.org/schema.json
will be stored as schema.json
. This naming allows for conflicts. If an attacker can get a user to run check-jsonschema
against a malicious schema URL, e.g., https://example.evil.org/schema.json
, they can insert their own schema into the cache and it will be picked up and used instead of the appropriate schema.
Such a cache confusion attack could be used to allow data to pass validation which should have been rejected.
A patch is in progress but has not yet been released.
--no-cache
to disable caching.--cache-filename
to select filenames for use in the cache, or to ensure that other usages do not overwrite the cached schema. (Note: this flag is being deprecated as part of the remediation effort.)curl -LOs https://example.org/schema.json; check-jsonschema --schemafile ./schema.json
{ "nvd_published_at": "2024-11-29T19:15:09Z", "cwe_ids": [ "CWE-349" ], "severity": "MODERATE", "github_reviewed": true, "github_reviewed_at": "2024-12-02T17:29:05Z" }