Code Injection in datamodel-code-generator (CVE-2026-54656)
Summary
Code injection in datamodel-code-generator (CVE-2026-54656). Successful exploitation can lead to full system takeover. Exploitable via validators. Mitigation: upgrade to 0.60.2 or later.
Original description
The description as published by the source.
Summary
When the Pydantic v2 output mode is in use, datamodel-code-generator reads a validators array from each model entry in the --extra-template-data file and synthesises a Pydantic @field_validator(...) decorator from each entry. The field names and the validator mode are interpolated into the decorator call wrapped in unescaped single quotes. A value containing ' breaks out of the string literal, letting an attacker emit an arbitrary positional Python expression into the decorator. The expression is evaluated at class-definition time, i.e. the moment the developer imports the generated module. This is the same trust model as the recently-published GHSA-wjv6-jcfj-mf9r (extras-file comment injection) but the impact is full RCE rather than a docstring leak.
Details
Sink: src/datamodel_code_generator/model/pydantic_v2/base_model.py, _process_validators (lines 405–449, at tag 0.60.1 / commit a321547e):
def _process_validators(self) -> None:
validators = self.extra_template_data.get("validators")
if not validators:
return
...
for validator in validators:
fields = validator.get("fields") or [validator.get("field")]
fields = [f for f in fields if f]
if not fields:
continue
function_path: str = validator["function"]
function_name = function_path.rsplit(".", 1)[-1]
mode = validator.get("mode", "after")
fields_str = ", ".join(f"'{f}'" for f in fields…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-54656 has been found in datamodel-code-generator.
Attackers can target a specific entry point like validators over the network to misuse the product.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: upgrade datamodel-code-generator to 0.60.2 or later.
If unsure, ask your IT team or search "datamodel-code-generator CVE-2026-54656" on the vendor's site.
CVE-2026-54656 (datamodel-code-generator) — CWE-94 / CVSS v3 7.8
Attack vector: local / unauthenticated
Attack surface: validators / _process_validators / a321547e / function_path
Patched: 0.60.2 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
Arbitrary code execution (CWE-94) exists in datamodel-code-generator. Attackers reach the vulnerable code path via validators without authentication.
Check the vendor advisory for the affected versions of datamodel-code-generator. Attack surface: validators / _process_validators / a321547e / function_path.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to 0.60.2.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'datamodel-code-generator' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'datamodel-code-generator' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
datamodel-code-generatorを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade datamodel-code-generator to 0.60.2ステージング環境で 0.60.2 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- package pypi.org
- web github.com
- web github.com
- web github.com