Vulnerability · Published Nov 29, 2024 · Assigned by GitHub_M
CVE-2024-53848check-jsonschema default caching for remote schemas allows for cache confusion
High 7.1
In plain English
A high-severity security flaw in check-jsonschema from python-jsonschema. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.1% (higher than 4% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
check-jsonschema is a CLI and set of pre-commit hooks for jsonschema validation. 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. This issue has been patched in version 0.30.0. All users are advised to upgrade. A few workarounds exist: 1. Users can use `--no-cache` to disable caching. 2. Users can use `--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.) 3. Users can explicitly download the schema before use as a local file, as in `curl -LOs https://example.org/schema.json; check-jsonschema --schemafile ./schema.json`
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | check-jsonschema | 0.30.0 | GHSA-q6mv-284r-mp36 |
| PyPI | check-jsonschema | 0.30.0 | PYSEC-2026-1245 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| python-jsonschema | check-jsonschema | < 0.30.0 |
Weakness: CWE-349 · Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N