MAVEN · JULY 2026 · EARLY WARNING

fastjson RCE Vulnerability (GHSA-CRF3-V9RR-V7HJ): Early Warning

EARLY WARNING · UNCONFIRMED. This page describes a developing threat that 0Day surfaced from early signals and has not yet independently confirmed. Details may change. Always verify against the primary sources before acting.
GHSA-CRF3-V9RR-V7HJSeverity: HIGH

An early warning has been issued for a remote code execution (RCE) vulnerability in fastjson versions 1.2.68 through 1.2.83.

What happened

An early warning has been issued regarding a remote code execution (RCE) vulnerability in fastjson versions 1.2.68 through 1.2.83. This vulnerability, tracked as GHSA-CRF3-V9RR-V7HJ, is reportedly exploitable under fastjson's default configuration. The issue is under investigation and has been assigned the internal classification of a critical CVE. No patch versions are currently available.

Professional software engineers using fastjson in their projects should assess their exposure by checking if their implementations use any of the affected versions (1.2.68 through 1.2.83). It is recommended to upgrade to a version beyond 1.2.83 or apply a patch if one becomes available. For the most accurate and up-to-date information, consult the primary sources listed below.

For more details, refer to the GitHub Advisory Database entry [GHSA-crf3-v9rr-v7hj](https://github.com/advisories/GHSA-crf3-v9rr-v7hj).

How 0Day mitigates this

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