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Hebrok, T.L. Storm, F.M. Cramer, M.M. Radoy, J. Somorovsky, in: 34th USENIX Security Symposium, 2025.","mla":"Hebrok, Sven Niclas, et al. “STEK Sharing Is Not Caring: Bypassing TLS Authentication in Web Servers Using Session Tickets.” <i>34th USENIX Security Symposium</i>, 2025.","apa":"Hebrok, S. N., Storm, T. L., Cramer, F. M., Radoy, M. M., &#38; Somorovsky, J. (2025). STEK Sharing is Not Caring: Bypassing TLS Authentication in Web Servers using Session Tickets. <i>34th USENIX Security Symposium</i>.","chicago":"Hebrok, Sven Niclas, Tim Leonhard Storm, Felix Matthias Cramer, Maximilian Manfred Radoy, and Juraj Somorovsky. “STEK Sharing Is Not Caring: Bypassing TLS Authentication in Web Servers Using Session Tickets.” In <i>34th USENIX Security Symposium</i>, 2025.","ieee":"S. N. Hebrok, T. L. Storm, F. M. Cramer, M. M. Radoy, and J. Somorovsky, “STEK Sharing is Not Caring: Bypassing TLS Authentication in Web Servers using Session Tickets,” 2025.","ama":"Hebrok SN, Storm TL, Cramer FM, Radoy MM, Somorovsky J. STEK Sharing is Not Caring: Bypassing TLS Authentication in Web Servers using Session Tickets. In: <i>34th USENIX Security Symposium</i>. ; 2025."},"year":"2025","has_accepted_license":"1","language":[{"iso":"eng"}],"file_date_updated":"2025-09-29T13:46:49Z","ddc":["000"],"user_id":"55616","department":[{"_id":"632"}],"_id":"60970","file":[{"creator":"snhebrok","date_created":"2025-09-29T13:41:18Z","date_updated":"2025-09-29T13:46:49Z","file_name":"paper.pdf","access_level":"open_access","file_id":"61465","file_size":333869,"content_type":"application/pdf","relation":"main_file"},{"content_type":"application/pdf","relation":"supplementary_material","date_updated":"2025-09-29T13:46:49Z","creator":"snhebrok","date_created":"2025-09-29T13:41:27Z","file_size":162464,"file_id":"61466","file_name":"ae.pdf","access_level":"open_access"},{"creator":"snhebrok","date_created":"2025-09-29T13:41:41Z","date_updated":"2025-09-29T13:46:49Z","file_id":"61467","file_name":"poster.pdf","access_level":"open_access","file_size":535577,"content_type":"application/pdf","relation":"poster"},{"relation":"slides","content_type":"application/pdf","file_id":"61468","file_name":"slides.pdf","access_level":"open_access","file_size":3057223,"date_created":"2025-09-29T13:42:04Z","creator":"snhebrok","date_updated":"2025-09-29T13:46:49Z"}],"status":"public","type":"conference","publication":"34th USENIX Security Symposium"},{"type":"book_chapter","publication":"Lecture Notes in Computer Science","status":"public","user_id":"68826","department":[{"_id":"632"}],"_id":"56079","language":[{"iso":"eng"}],"publication_status":"published","publication_identifier":{"issn":["0302-9743","1611-3349"],"isbn":["9783031708954","9783031708961"]},"citation":{"bibtex":"@inbook{Radoy_Hebrok_Somorovsky_2024, place={Cham}, title={In Search of Partitioning Oracle Attacks Against TLS Session Tickets}, DOI={<a href=\"https://doi.org/10.1007/978-3-031-70896-1_16\">10.1007/978-3-031-70896-1_16</a>}, booktitle={Lecture Notes in Computer Science}, publisher={Springer Nature Switzerland}, author={Radoy, Maximilian Manfred and Hebrok, Sven Niclas and Somorovsky, Juraj}, year={2024} }","short":"M.M. Radoy, S.N. Hebrok, J. Somorovsky, in: Lecture Notes in Computer Science, Springer Nature Switzerland, Cham, 2024.","mla":"Radoy, Maximilian Manfred, et al. “In Search of Partitioning Oracle Attacks Against TLS Session Tickets.” <i>Lecture Notes in Computer Science</i>, Springer Nature Switzerland, 2024, doi:<a href=\"https://doi.org/10.1007/978-3-031-70896-1_16\">10.1007/978-3-031-70896-1_16</a>.","apa":"Radoy, M. M., Hebrok, S. N., &#38; Somorovsky, J. (2024). In Search of Partitioning Oracle Attacks Against TLS Session Tickets. In <i>Lecture Notes in Computer Science</i>. Springer Nature Switzerland. <a href=\"https://doi.org/10.1007/978-3-031-70896-1_16\">https://doi.org/10.1007/978-3-031-70896-1_16</a>","ama":"Radoy MM, Hebrok SN, Somorovsky J. In Search of Partitioning Oracle Attacks Against TLS Session Tickets. In: <i>Lecture Notes in Computer Science</i>. Springer Nature Switzerland; 2024. doi:<a href=\"https://doi.org/10.1007/978-3-031-70896-1_16\">10.1007/978-3-031-70896-1_16</a>","ieee":"M. M. Radoy, S. N. Hebrok, and J. Somorovsky, “In Search of Partitioning Oracle Attacks Against TLS Session Tickets,” in <i>Lecture Notes in Computer Science</i>, Cham: Springer Nature Switzerland, 2024.","chicago":"Radoy, Maximilian Manfred, Sven Niclas Hebrok, and Juraj Somorovsky. “In Search of Partitioning Oracle Attacks Against TLS Session Tickets.” In <i>Lecture Notes in Computer Science</i>. Cham: Springer Nature Switzerland, 2024. <a href=\"https://doi.org/10.1007/978-3-031-70896-1_16\">https://doi.org/10.1007/978-3-031-70896-1_16</a>."},"year":"2024","place":"Cham","date_created":"2024-09-06T07:06:14Z","author":[{"orcid":"0009-0005-3059-6823","last_name":"Radoy","id":"68826","full_name":"Radoy, Maximilian Manfred","first_name":"Maximilian Manfred"},{"first_name":"Sven Niclas","orcid":"0009-0006-1172-1665","last_name":"Hebrok","id":"55616","full_name":"Hebrok, Sven Niclas"},{"first_name":"Juraj","full_name":"Somorovsky, Juraj","id":"83504","orcid":"0000-0002-3593-7720","last_name":"Somorovsky"}],"date_updated":"2024-10-07T13:38:28Z","publisher":"Springer Nature Switzerland","doi":"10.1007/978-3-031-70896-1_16","title":"In Search of Partitioning Oracle Attacks Against TLS Session Tickets"},{"conference":{"location":"Hawaii","end_date":"2024-12-13","start_date":"2024-12-09","name":"Annual Computer Security Applications Conference"},"title":"TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations","author":[{"last_name":"Bäumer","full_name":"Bäumer, Fabian","first_name":"Fabian"},{"full_name":"Brinkmann, Marcus","last_name":"Brinkmann","first_name":"Marcus"},{"last_name":"Erinola","full_name":"Erinola, Nurullah","first_name":"Nurullah"},{"orcid":"0009-0006-1172-1665","last_name":"Hebrok","id":"55616","full_name":"Hebrok, Sven Niclas","first_name":"Sven Niclas"},{"last_name":"Heitmann","orcid":"0009-0003-7687-7044","id":"74619","full_name":"Heitmann, Nico","first_name":"Nico"},{"last_name":"Lange","id":"67893","full_name":"Lange, Felix","first_name":"Felix"},{"full_name":"Maehren, Marcel","last_name":"Maehren","first_name":"Marcel"},{"last_name":"Merget","full_name":"Merget, Robert","first_name":"Robert"},{"id":"63563","full_name":"Niere, Niklas","last_name":"Niere","first_name":"Niklas"},{"id":"68826","full_name":"Radoy, Maximilian Manfred","last_name":"Radoy","orcid":"0009-0005-3059-6823","first_name":"Maximilian Manfred"},{"first_name":"Conrad","last_name":"Schmidt","full_name":"Schmidt, Conrad"},{"first_name":"Jörg","last_name":"Schwenk","full_name":"Schwenk, Jörg"},{"first_name":"Juraj","last_name":"Somorovsky","orcid":"0000-0002-3593-7720","full_name":"Somorovsky, Juraj","id":"83504"}],"date_created":"2024-12-17T11:25:14Z","date_updated":"2025-02-27T08:02:30Z","citation":{"ama":"Bäumer F, Brinkmann M, Erinola N, et al. TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations. In: <i>Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24)</i>. ; 2024.","chicago":"Bäumer, Fabian, Marcus Brinkmann, Nurullah Erinola, Sven Niclas Hebrok, Nico Heitmann, Felix Lange, Marcel Maehren, et al. “TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations.” In <i>Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24)</i>, 2024.","ieee":"F. Bäumer <i>et al.</i>, “TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations,” presented at the Annual Computer Security Applications Conference, Hawaii, 2024.","apa":"Bäumer, F., Brinkmann, M., Erinola, N., Hebrok, S. N., Heitmann, N., Lange, F., Maehren, M., Merget, R., Niere, N., Radoy, M. M., Schmidt, C., Schwenk, J., &#38; Somorovsky, J. (2024). TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations. <i>Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24)</i>. Annual Computer Security Applications Conference, Hawaii.","short":"F. Bäumer, M. Brinkmann, N. Erinola, S.N. Hebrok, N. Heitmann, F. Lange, M. Maehren, R. Merget, N. Niere, M.M. Radoy, C. Schmidt, J. Schwenk, J. Somorovsky, in: Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24), 2024.","bibtex":"@inproceedings{Bäumer_Brinkmann_Erinola_Hebrok_Heitmann_Lange_Maehren_Merget_Niere_Radoy_et al._2024, title={TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations}, booktitle={Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24)}, author={Bäumer, Fabian and Brinkmann, Marcus and Erinola, Nurullah and Hebrok, Sven Niclas and Heitmann, Nico and Lange, Felix and Maehren, Marcel and Merget, Robert and Niere, Niklas and Radoy, Maximilian Manfred and et al.}, year={2024} }","mla":"Bäumer, Fabian, et al. “TLS-Attacker: A Dynamic Framework for Analyzing TLS Implementations.” <i>Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24)</i>, 2024."},"year":"2024","quality_controlled":"1","language":[{"iso":"eng"}],"keyword":["SSL","TLS","DTLS","Protocol State Fuzzing","Planning Based"],"user_id":"67893","department":[{"_id":"632"}],"_id":"57816","status":"public","abstract":[{"lang":"eng","text":"TLS-Attacker is an open-source framework for analyzing Transport\r\nLayer Security (TLS) implementations. The framework allows users\r\nto specify custom protocol flows and provides modification hooks to\r\nmanipulate message contents. Since its initial publication in 2016 by\r\nJuraj Somorovsky, TLS-Attacker has been used in numerous studies\r\npublished at well-established conferences and helped to identify\r\nvulnerabilities in well-known open-source TLS libraries. To enable\r\nautomated analyses, TLS-Attacker has grown into a suite of projects,\r\neach designed as a building block that can be applied to facilitate\r\nvarious analysis methodologies. The framework still undergoes\r\ncontinuous improvements with feature extensions, such as DTLS\r\n1.3 or the addition of new dialects such as QUIC, to continue its\r\neffectiveness and relevancy as a security analysis framework."}],"type":"conference","publication":"Proceedings of Cybersecurity Artifacts Competition and Impact Award (ACSAC ’24)"},{"title":"Poster: Circumventing the GFW with TLS Record Fragmentation","doi":"10.1145/3576915.3624372","publisher":"ACM","date_updated":"2024-04-02T12:17:18Z","author":[{"full_name":"Niere, Niklas","id":"63563","last_name":"Niere","first_name":"Niklas"},{"id":"55616","full_name":"Hebrok, Sven Niclas","last_name":"Hebrok","orcid":"0009-0006-1172-1665","first_name":"Sven Niclas"},{"id":"83504","full_name":"Somorovsky, Juraj","last_name":"Somorovsky","orcid":"0000-0002-3593-7720","first_name":"Juraj"},{"first_name":"Robert","full_name":"Merget, Robert","last_name":"Merget"}],"date_created":"2023-12-15T07:34:24Z","year":"2023","citation":{"ieee":"N. Niere, S. N. Hebrok, J. Somorovsky, and R. Merget, “Poster: Circumventing the GFW with TLS Record Fragmentation,” 2023, doi: <a href=\"https://doi.org/10.1145/3576915.3624372\">10.1145/3576915.3624372</a>.","chicago":"Niere, Niklas, Sven Niclas Hebrok, Juraj Somorovsky, and Robert Merget. “Poster: Circumventing the GFW with TLS Record Fragmentation.” In <i>Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security</i>. ACM, 2023. <a href=\"https://doi.org/10.1145/3576915.3624372\">https://doi.org/10.1145/3576915.3624372</a>.","ama":"Niere N, Hebrok SN, Somorovsky J, Merget R. Poster: Circumventing the GFW with TLS Record Fragmentation. In: <i>Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security</i>. ACM; 2023. doi:<a href=\"https://doi.org/10.1145/3576915.3624372\">10.1145/3576915.3624372</a>","apa":"Niere, N., Hebrok, S. N., Somorovsky, J., &#38; Merget, R. (2023). Poster: Circumventing the GFW with TLS Record Fragmentation. <i>Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security</i>. <a href=\"https://doi.org/10.1145/3576915.3624372\">https://doi.org/10.1145/3576915.3624372</a>","short":"N. Niere, S.N. Hebrok, J. Somorovsky, R. Merget, in: Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security, ACM, 2023.","bibtex":"@inproceedings{Niere_Hebrok_Somorovsky_Merget_2023, title={Poster: Circumventing the GFW with TLS Record Fragmentation}, DOI={<a href=\"https://doi.org/10.1145/3576915.3624372\">10.1145/3576915.3624372</a>}, booktitle={Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security}, publisher={ACM}, author={Niere, Niklas and Hebrok, Sven Niclas and Somorovsky, Juraj and Merget, Robert}, year={2023} }","mla":"Niere, Niklas, et al. “Poster: Circumventing the GFW with TLS Record Fragmentation.” <i>Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security</i>, ACM, 2023, doi:<a href=\"https://doi.org/10.1145/3576915.3624372\">10.1145/3576915.3624372</a>."},"publication_status":"published","language":[{"iso":"eng"}],"_id":"49654","department":[{"_id":"632"}],"user_id":"83504","abstract":[{"text":"State actors around the world censor the HTTPS protocol to block access to certain websites. While many circumvention strategies utilize the TCP layer only little emphasis has been placed on the analysis of TLS-a complex protocol and integral building block of HTTPS. In contrast to the TCP layer, circumvention methods on the TLS layer do not require root privileges since TLS operates on the application layer. With this proposal, we want to motivate a deeper analysis of TLS in regard to censorship circumvention techniques. To prove the existence of such techniques, we present TLS record fragmentation as a novel circumvention technique and circumvent the Great Firewall of China (GFW) using this technique. We hope that our research fosters collaboration between censorship and TLS researchers.","lang":"eng"}],"status":"public","publication":"Proceedings of the 2023 ACM SIGSAC Conference on Computer and Communications Security","type":"conference"},{"title":"We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets","main_file_link":[{"open_access":"1","url":"https://www.usenix.org/conference/usenixsecurity23/presentation/hebrok"}],"oa":"1","date_updated":"2023-06-21T06:49:56Z","author":[{"first_name":"Sven Niclas","last_name":"Hebrok","full_name":"Hebrok, Sven Niclas","id":"55616"},{"first_name":"Simon","last_name":"Nachtigall","full_name":"Nachtigall, Simon"},{"full_name":"Maehren, Marcel","last_name":"Maehren","first_name":"Marcel"},{"first_name":"Nurullah","last_name":"Erinola","full_name":"Erinola, Nurullah"},{"first_name":"Robert","full_name":"Merget, Robert","last_name":"Merget"},{"first_name":"Juraj","orcid":"0000-0002-3593-7720","last_name":"Somorovsky","full_name":"Somorovsky, Juraj","id":"83504"},{"first_name":"Jörg","full_name":"Schwenk, Jörg","last_name":"Schwenk"}],"date_created":"2023-03-22T08:15:42Z","year":"2023","citation":{"ama":"Hebrok SN, Nachtigall S, Maehren M, et al. We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets. In: <i>32nd USENIX Security Symposium</i>. ; 2023.","chicago":"Hebrok, Sven Niclas, Simon Nachtigall, Marcel Maehren, Nurullah Erinola, Robert Merget, Juraj Somorovsky, and Jörg Schwenk. “We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets.” In <i>32nd USENIX Security Symposium</i>, 2023.","ieee":"S. N. Hebrok <i>et al.</i>, “We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets,” 2023.","apa":"Hebrok, S. N., Nachtigall, S., Maehren, M., Erinola, N., Merget, R., Somorovsky, J., &#38; Schwenk, J. (2023). We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets. <i>32nd USENIX Security Symposium</i>.","bibtex":"@inproceedings{Hebrok_Nachtigall_Maehren_Erinola_Merget_Somorovsky_Schwenk_2023, title={We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets}, booktitle={32nd USENIX Security Symposium}, author={Hebrok, Sven Niclas and Nachtigall, Simon and Maehren, Marcel and Erinola, Nurullah and Merget, Robert and Somorovsky, Juraj and Schwenk, Jörg}, year={2023} }","short":"S.N. Hebrok, S. Nachtigall, M. Maehren, N. Erinola, R. Merget, J. Somorovsky, J. Schwenk, in: 32nd USENIX Security Symposium, 2023.","mla":"Hebrok, Sven Niclas, et al. “We Really Need to Talk About Session Tickets: A Large-Scale Analysis of Cryptographic Dangers with TLS Session Tickets.” <i>32nd USENIX Security Symposium</i>, 2023."},"language":[{"iso":"eng"}],"_id":"43060","department":[{"_id":"632"}],"user_id":"83504","status":"public","publication":"32nd USENIX Security Symposium","type":"conference"},{"publication":"31st USENIX Security Symposium (USENIX Security 22)","type":"conference","status":"public","_id":"32573","department":[{"_id":"632"}],"user_id":"83504","language":[{"iso":"eng"}],"year":"2022","place":"Boston, MA","citation":{"apa":"Maehren, M., Nieting, P., Hebrok, S. N., Merget, R., Somorovsky, J., &#38; Schwenk, J. (2022). TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries. <i>31st USENIX Security Symposium (USENIX Security 22)</i>.","mla":"Maehren, Marcel, et al. “TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries.” <i>31st USENIX Security Symposium (USENIX Security 22)</i>, USENIX Association, 2022.","bibtex":"@inproceedings{Maehren_Nieting_Hebrok_Merget_Somorovsky_Schwenk_2022, place={Boston, MA}, title={TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries}, booktitle={31st USENIX Security Symposium (USENIX Security 22)}, publisher={USENIX Association}, author={Maehren, Marcel and Nieting, Philipp and Hebrok, Sven Niclas and Merget, Robert and Somorovsky, Juraj and Schwenk, Jörg}, year={2022} }","short":"M. Maehren, P. Nieting, S.N. Hebrok, R. Merget, J. Somorovsky, J. Schwenk, in: 31st USENIX Security Symposium (USENIX Security 22), USENIX Association, Boston, MA, 2022.","ama":"Maehren M, Nieting P, Hebrok SN, Merget R, Somorovsky J, Schwenk J. TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries. In: <i>31st USENIX Security Symposium (USENIX Security 22)</i>. USENIX Association; 2022.","ieee":"M. Maehren, P. Nieting, S. N. Hebrok, R. Merget, J. Somorovsky, and J. Schwenk, “TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries,” 2022.","chicago":"Maehren, Marcel, Philipp Nieting, Sven Niclas Hebrok, Robert Merget, Juraj Somorovsky, and Jörg Schwenk. “TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries.” In <i>31st USENIX Security Symposium (USENIX Security 22)</i>. Boston, MA: USENIX Association, 2022."},"publisher":"USENIX Association","date_updated":"2024-04-02T12:19:45Z","date_created":"2022-08-03T11:03:30Z","author":[{"full_name":"Maehren, Marcel","last_name":"Maehren","first_name":"Marcel"},{"first_name":"Philipp","full_name":"Nieting, Philipp","last_name":"Nieting"},{"first_name":"Sven Niclas","full_name":"Hebrok, Sven Niclas","id":"55616","last_name":"Hebrok","orcid":"0009-0006-1172-1665"},{"last_name":"Merget","full_name":"Merget, Robert","first_name":"Robert"},{"full_name":"Somorovsky, Juraj","id":"83504","orcid":"0000-0002-3593-7720","last_name":"Somorovsky","first_name":"Juraj"},{"first_name":"Jörg","full_name":"Schwenk, Jörg","last_name":"Schwenk"}],"title":"TLS-Anvil: Adapting Combinatorial Testing for TLS Libraries"}]