The three volume set LNCS 13554, 13555, 13556 constitutes the proceedings of the 27th European Symposium on Research in Computer Security, ESORICS 2022, which took place in September 2022. The conference took place in Copenhagen, Denmark, in a hybrid mode.The 104 full papers and 6 poster papers presented in these proceedings were carefully reviewed and selected from 562 submissions. They were organized in topical sections as follows:Part I: Blockchain security; privacy; crypto; attacks; sidechannels; Part II: Anonymity; cloud security; access control; authentication; digital signatures; IoT security; applications;Part III: Formal analysis; Web security; hardware security; multiparty computation; ML techniques; cyber-physical systems security; network and software security; posters.