CVE-2026-55391 datamodel-code-generator vulnerable to SSRF protection bypass via DNS rebinding
Attackers can bypass SSRF protections via DNS rebinding to access internal services when using datamodel-code-generator to fetch remote schemas.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-55391?
CVE-2026-55391 is a high-severity server-side request forgery vulnerability in koxudaxi datamodel-code-generator, published on 28 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
datamodel-code-generator generates Pydantic v2 models, dataclasses, TypedDict, and msgspec.Struct from OpenAPI, JSON Schema, GraphQL, Avro, Protobuf, and raw JSON, YAML, or CSV. Prior to 0.63.0, datamodel-code-generator validates a URL host once in src/datamodel_code_generator/http.py through get_body, _validate_url_for_fetch, and _get_ips_from_host, but then lets httpx resolve the host again for the connection, allowing DNS rebinding to bypass allow_private_network=False and reach internal services. This issue is fixed in version 0.63.0.
Which versions are affected by CVE-2026-55391?
3 open source packages ship an affected version, including datamodel-code-generator. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
datamodel-code-generator PyPI | All versions | 0.63.0 |
datamodel-code-generator PyPI | All versions | 0.63.0 |
datamodel-code-generator PyPI | All versions | 0.63.0 |
Products include Koxudaxi Datamodel-Code-Generator.
How do I fix CVE-2026-55391?
Upgrade datamodel-code-generator to 0.63.0 or later.
Upgrade, and send outbound requests through an allow-list that blocks internal addresses. More about Server-side request forgery.
Is CVE-2026-55391 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55391 exists.
Other vulnerabilities in koxudaxi datamodel-code-generator
- CVE-2026-54653 `datamodel-code-generator` vulnerable to code injection in via attacker-controlled `default_factory` schema field
- CVE-2026-54690 datamodel-code-generator vulnerable to SSRF via JSON-Schema `$ref` to HTTP URL (silent by default)
- CVE-2026-54656 `datamodel-code-generator` vulnerable to code execution on import via unescaped `validators` entries in --extra-template-data
- CVE-2026-55389 datamodel-code-generator vulnerable to arbitrary local file read via JSON-Schema `$ref` (`file://` and `../` traversal), bypassing `--no-allow-remote-refs`
- CVE-2026-55415 datamodel-code-generator vulnerable to code injection via `x-python-import` / `customTypePath` in generated import statements
Sources
Also known as GHSA-vx7x-vcc2-c44g, MINI-x22q-928f-qm5g, PYSEC-2026-3565.