Django REST framework: JSONParser applies an attacker-named codec to the request stream

Why it is Amber

• CVSS 7.5 high
• Remotely exploitable without logging in
• On your watchlist: PyPI

Affected packages

References

• https://github.com/advisories/GHSA-3547-9m27-7rxg
• https://github.com/encode/django-rest-framework/security/advisories/GHSA-3547-9m27-7rxg
• https://nvd.nist.gov/vuln/detail/CVE-2026-114136
• https://github.com/encode/django-rest-framework/commit/3c2634599b26a9f789b03045118dbc276117611a
• https://github.com/encode/django-rest-framework/releases/tag/3.18.2
• https://github.com/advisories/GHSA-3547-9m27-7rxg

Original description

Django REST framework is a toolkit for building Web APIs. From 3.6.4 until 3.18.2, JSONParser.parse in rest_framework/parsers.py uses the client-supplied Content-Type charset value with codecs.getreader, which accepts byte-transform codecs such as bz2_codec rather than only text encodings. A remote unauthenticated client can therefore cause a compressed JSON request body to be expanded after Django has enforced DATA_UPLOAD_MAX_MEMORY_SIZE against only the wire bytes, allowing a very small request to consume substantial per-worker memory. The default parser set is sufficient, and any reachable endpoint that accepts a JSON body is affected. This issue is fixed in version 3.18.2.