Description

Fastjson before 1.2.48 mishandles autoType because, when an @type key is in a JSON document, and the value of that key is the name of a Java class, there may be calls to certain public methods of that class. Depending on the behavior of those methods, there may be JNDI injection with an attacker-supplied payload located elsewhere in that JSON document. This was exploited in the wild in 2023 through 2025. NOTE: this issue exists because of an incomplete fix for CVE-2017-18349. Also, a later bypass is covered by CVE-2022-25845.

Weaknesses 1

References 7

• cert.360.cn https://cert.360.cn/warning/detail?id=7240aeab581c6dc2c9c5350756079955
• github.com https://github.com/alibaba/fastjson/compare/1.2.47...1.2.48
• github.com https://github.com/vulhub/vulhub/tree/master/fastjson/1.2.47-rce
• cloudsek.com https://www.cloudsek.com/blog/androxgh0st-continues-exploitation-operators-compromise-a-us-university-for-hosting-c2-logger
• cnvd.org.cn https://www.cnvd.org.cn/flaw/show/CNVD-2019-22238
• freebuf.com https://www.freebuf.com/vuls/208339.html
• seebug.org https://www.seebug.org/vuldb/ssvid-98020

Remediation