Critical (9.8) in antfin sofa-hessian. EPSS 0.7% chance of exploitation in the next 30 days. Fixed in com.alipay.sofa:hessian 3.5.5.
sofa-hessian is an internal improved version of Hessian3/4 powered by Ant Group CO., Ltd. The SOFA Hessian protocol uses a blacklist mechanism to restrict deserialization of potentially dangerous classes for security protection. But there is a gadget chain that can bypass the SOFA Hessian blacklist protection mechanism, and this gadget chain only relies on JDK and does not rely on any third-party components. This issue is fixed by an update to the blacklist, users can upgrade to sofahessian version 3.5.5 to avoid this issue. Users unable to upgrade may maintain a blacklist themselves in the directory `external/serialize.blacklist`.
Severity
CVSS 3.1
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
0.7% chance of exploitation in the next 30 days; higher than 52% of CVEs (scores of 2026-10-31)