---
id: CVE-2024-53848
aliases:
  - GHSA-q6mv-284r-mp36
  - PYSEC-2026-1245
title: check-jsonschema default caching for remote schemas allows for cache confusion
summary: check-jsonschema default caching for remote schemas allows for cache confusion
severity: high
cvss: 7.1
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:H/A:N'
vendor: check-jsonschema
product: check-jsonschema
ecosystem: pip
affected:
  - check-jsonschema < 0.30.0
patched:
  - check-jsonschema 0.30.0
published: '2024-12-02'
updated: '2026-07-07'
source: OSV
sourceUrl: 'https://osv.dev/vulnerability/GHSA-q6mv-284r-mp36'
references:
  - url: >-
      https://github.com/python-jsonschema/check-jsonschema/security/advisories/GHSA-q6mv-284r-mp36
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2024-53848'
  - url: >-
      https://github.com/python-jsonschema/check-jsonschema/commit/c52714b85e6725b1b24516fbdedacb333b939152
  - url: 'https://github.com/python-jsonschema/check-jsonschema'
tags:
  - osv
  - pip
epss: 0.00145
epssPercentile: 0.03106
ingestedAt: '2026-07-08T18:25:52.109Z'
---

## Overview

### Impact

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.

### Patches

A patch is in progress but has not yet been released.

### Workarounds

- Users can use `--no-cache` to disable caching.
- 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.)
- 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

- `check-jsonschema < 0.30.0`

## Remediation

Upgrade to a patched release:

- `check-jsonschema 0.30.0`