CVE-2026-16723 PUBLISHED

Remote Code Execution in fastjson 1.2.68–1.2.83

Assigner: alibaba
Reserved: 23.07.2026 Published: 23.07.2026 Updated: 23.07.2026

A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83. This vulnerability is exploitable under fastjson's stock default configuration — no AutoType enablement required, no classpath gadget required.

Metrics

CVSS 3.1

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CVSS Score: 9

Attack Vector	Network	Scope	Changed
Attack Complexity	High	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	None	Availability Impact	High

CVSS 3.1

Product Status

Vendor	Alibaba
Product	Fastjson
Versions	Default: unaffected affected from 1.2.68 to 1.2.83 (incl.)

Credits

Kirill Firsov of FearsOff Cybersecurity finder

References

https://github.com/alibaba/fastjson2/wiki/Security-Advisory:-Remote-Code-Execution-in-fastjson-1.2.68%E2%80%931.2.83

Problem Types

CWE-20 Improper input validation CWE
CWE-502 Deserialization of untrusted data CWE

Impacts

CAPEC-586 Object Injection