ERB has an @_init deserialization guard bypass via def_module / def_method / def_class

Summary Ruby 2.7.0 before ERB 2.2.0 was published on rubygems.org introduced an @init instance variable guard in ERBresult and ERBrun to prevent code execution when an ERB object is reconstructed via Marshal.load deserialization. However, three other public methods that also evaluate @src via eva...

GHSA-Q339-8RMV-2MHV ERB has an @_init deserialization guard bypass via def_module / def_method / def_class

Summary Ruby 2.7.0 before ERB 2.2.0 was published on rubygems.org introduced an @init instance variable guard in ERBresult and ERBrun to prevent code execution when an ERB object is reconstructed via Marshal.load deserialization. However, three other public methods that also evaluate @src via eva...

CVE-2026-41316 ERB has an @_init deserialization guard bypass via def_module / def_method / def_class

ERB is a templating system for Ruby. Ruby 2.7.0 before ERB 2.2.0 was published on rubygems.org introduced an @init instance variable guard in ERBresult and ERBrun to prevent code execution when an ERB object is reconstructed via Marshal.load deserialization. However, three other public methods th...

CVE-2026-41316 ERB has an @_init deserialization guard bypass via def_module / def_method / def_class

ERB is a templating system for Ruby. Ruby 2.7.0 before ERB 2.2.0 was published on rubygems.org introduced an @init instance variable guard in ERBresult and ERBrun to prevent code execution when an ERB object is reconstructed via Marshal.load deserialization. However, three other public methods th...

CVE-2026-41316

ERB has a deserialization guard for @_init in ERB#result and ERB#run, but public methods ERB#def_method, ERB#def_module, and ERB#def_class were not guarded. The vulnerability arises when Marshal.load is used on untrusted data with erb loaded, allowing code execution via the unguarded paths. Patch...

ERB has an @_init deserialization guard bypass via def_module / def_method / def_class

ERB implements an @init guard to prevent code execution when ERB objects are reconstructed via Marshal.load on untrusted data. However, ERBdefmethod, ERBdefmodule, and ERBdefclass evaluate the template source without checking this guard, allowing an attacker who controls the data passed to...

ERB has an @_init deserialization guard bypass via def_module / def_method / def_class

ERB implements an @init guard to prevent code execution when ERB objects are reconstructed via Marshal.load on untrusted data. However, ERBdefmethod, ERBdefmodule, and ERBdefclass evaluate the template source without checking this guard, allowing an attacker who controls the data passed to...