CINXE.COM
Security of the Ascon Authenticated Encryption Mode in the Presence of Quantum Adversaries
<!DOCTYPE html> <html lang="en"> <head> <meta charset="utf-8"> <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no"> <link href="/css/dist/css/bootstrap.min.css" rel="stylesheet"> <title>Security of the Ascon Authenticated Encryption Mode in the Presence of Quantum Adversaries</title> <link rel="stylesheet" href="/css/eprint.css?v=10"> <link rel="shortcut icon" href="/favicon.ico" type="image/x-icon" /> <link rel="apple-touch-icon" href="/img/apple-touch-icon-180x180.png" /> <style> a.toggle-open:after { content:' -'; font-weight: 800; } a.toggle-closed:after { content: " ›"; font-weight: 800; } .paper-abstract { white-space: pre-wrap; } #metadata dt { margin-top: 1rem; } #metadata dt + dd { /* gap between dt and first dd */ margin-top: .75rem; } #metadata dd { margin-left: 2rem; } #metadata dd.keywords { padding-bottom: .5rem; } span.authorName { margin-top: .5rem; font-style: italic; } </style> <script> MathJax = { tex: { inlineMath: [['$', '$'], ['\\(', '\\)']], displayMath: [ ['$$','$$'], ["\\[","\\]"] ], processEnvironments: false }, loader: { load: [ "ui/safe", "ui/lazy", ], }, options: { safeOptions: { allow: { URLs: "none", classes: "safe", cssIDs: "safe", styles: "safe", }, }, } }; </script> <script id="MathJax-script" async src="/js/mathjax/tex-chtml.js"></script> <meta name="citation_title" content="Security of the Ascon Authenticated Encryption Mode in the Presence of Quantum Adversaries"> <meta name="citation_author" content="Nathalie Lang"> <meta name="citation_author" content="Stefan Lucks"> <meta name="citation_author" content="Bart Mennink"> <meta name="citation_author" content="Suprita Talnikar"> <meta name="citation_journal_title" content="Cryptology ePrint Archive"> <meta name="citation_publication_date" content="2025"> <meta name="citation_pdf_url" content="https://eprint.iacr.org/2025/411.pdf"> <meta property="og:image" content="https://eprint.iacr.org/img/iacrlogo.png"/> <meta property="og:image:alt" content="IACR logo"/> <meta property="og:url" content="https://eprint.iacr.org/2025/411"> <meta property="og:site_name" content="IACR Cryptology ePrint Archive" /> <meta property="og:type" content="article" /> <meta property="og:title" content="Security of the Ascon Authenticated Encryption Mode in the Presence of Quantum Adversaries" /> <meta property="og:description" content="We examine the post-quantum security of the Ascon authenticated encryption (AE) mode. In spite of comprehensive research of Ascon's classical security, the potential impact of quantum adversaries on Ascon has not yet been explored much. We investigate the generic security of the Ascon AE mode in the setting where the adversary owns a quantum computer to improve its attack, while the adversarial encryption or decryption queries are still classical. In this so-called Q1 model, Ascon achieves security up to approximately $\min\{2^{c/3},2^{k/2}\}$ evaluations, where $c$ is the capacity, $k$ the key size, and the adversary is block-wise adaptive but restricted to one forgery attempt. Our technique is based on applying the semi-classical one-way to hiding (O2H) lemma, and on tailoring the puncture set to the Ascon mode. Additionally, we discuss different parameter choices for Ascon and compare our results to generic quantum attacks, such as Grover-based key search and state recovery." /> <meta property="article:section" content="SECRETKEY" /> <meta property="article:modified_time" content="2025-03-04T13:06:35+00:00" /> <meta property="article:published_time" content="2025-03-04T13:06:35+00:00" /> <meta property="article:tag" content="post-quantum security" /> <meta property="article:tag" content="lightweight cryptography" /> <meta property="article:tag" content="Ascon" /> <meta property="article:tag" content="authenticated encryption" /> </head> <body> <noscript> <h1 class="text-center">What a lovely hat</h1> <h4 class="text-center">Is it made out of <a href="https://iacr.org/tinfoil.html">tin foil</a>?</h4> </noscript> <div class="fixed-top" id="topNavbar"> <nav class="navbar navbar-custom navbar-expand-lg"> <div class="container px-0 justify-content-between justify-content-lg-evenly"> <div class="order-0 align-items-center d-flex"> <button class="navbar-toggler btnNoOutline" type="button" data-bs-toggle="collapse" data-bs-target="#navbarContent" aria-controls="navbarContent" aria-expanded="false"> <span class="icon-bar top-bar"></span> <span class="icon-bar middle-bar"></span> <span class="icon-bar bottom-bar"></span> </button> <a class="d-none me-5 d-lg-inline" href="https://iacr.org/"><img class="iacrlogo" src="/img/iacrlogo_small.png" alt="IACR Logo" style="max-width:6rem;"></a> </div> <a class="ePrintname order-1" href="/"> <span class="longNavName">Cryptology ePrint Archive</span> </a> <div class="collapse navbar-collapse order-3" id="navbarContent"> <ul class="navbar-nav me-auto ms-2 mb-2 mb-lg-0 justify-content-end w-100"> <li class="ps-md-3 nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false"> Papers </a> <ul class="dropdown-menu me-3" aria-labelledby="navbarDropdown"> <span class="text-dark mx-3" style="white-space:nowrap;">Updates from the last:</span> <li><a class="dropdown-item ps-custom" href="/days/7">7 days</a></li> <li><a class="dropdown-item ps-custom" href="/days/31">31 days</a></li> <li><a class="dropdown-item ps-custom" href="/days/183">6 months</a></li> <li><a class="dropdown-item ps-custom" href="/days/365">365 days</a></li> <li><hr class="dropdown-divider"></li> <li><a class="dropdown-item" href="/byyear">Listing by year</a></li> <li><a class="dropdown-item" href="/complete">All papers</a></li> <li><a class="dropdown-item" href="/complete/compact">Compact view</a></li> <li><a class="dropdown-item" href="https://www.iacr.org/news/subscribe">Subscribe</a></li> <li><hr class="dropdown-divider"></li> <li><a class="dropdown-item" href="/citation.html">How to cite</a></li> <li><hr class="dropdown-divider"></li> <li><a class="dropdown-item" href="/rss">Harvesting metadata</a></li> </ul> </li> <li class="ps-md-3 nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="submissionsDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false"> Submissions </a> <ul class="dropdown-menu me-3" aria-labelledby="submissionsDropdown"> <li><a class="dropdown-item" href="/submit">Submit a paper</a></li> <li><a class="dropdown-item" href="/revise">Revise or withdraw a paper</a></li> <li><a class="dropdown-item" href="/operations.html">Acceptance and publishing conditions</a></li> </ul> </li> <li class="ps-md-3 nav-item dropdown"> <a class="nav-link dropdown-toggle" href="#" id="aboutDropdown" role="button" data-bs-toggle="dropdown" aria-expanded="false"> About </a> <ul class="dropdown-menu me-3" aria-labelledby="aboutDropdown"> <li><a class="dropdown-item" href="/about.html">Goals and history</a></li> <li><a class="dropdown-item" href="/news.html">News</a></li> <li><a class="dropdown-item" href="/stats">Statistics</a></li> <li><a class="dropdown-item" href="/contact.html">Contact</a></li> </ul> </li> </ul> </div> <div class="dropdown ps-md-2 text-right order-2 order-lg-last"> <button class="btn btnNoOutline" type="button" id="dropdownMenuButton1" data-bs-toggle="dropdown" aria-expanded="false"> <img src="/img/search.svg" class="searchIcon" alt="Search Button"/> </button> <div id="searchDd" class="dropdown-menu dropdown-menu-end p-0" aria-labelledby="dropdownMenuButton1"> <form action="/search" method="GET"> <div class="input-group"> <input id="searchbox" name="q" type="search" class="form-control" autocomplete="off"> <button class="btn btn-secondary border input-group-append ml-2"> Search </button> </div> </form> <div class="ms-2 p-1 d-none"><a href="/search">Advanced search</a></div> </div> </div> </div> </nav> </div> <main id="eprintContent" class="container px-3 py-4 p-md-4"> <div class="row mt-4"> <div class="col-md-7 col-lg-8 pe-md-5"> <h4>Paper 2025/411</h4> <h3 class="mb-3">Security of the Ascon Authenticated Encryption Mode in the Presence of Quantum Adversaries</h3> <div class="author"><span class="authorName">Nathalie Lang</span><a class="ms-1" target="_blank" href="https://orcid.org/0000-0002-2768-9878"><img class="align-baseline orcidIcon" src="/img/orcid.svg"></a><span class="affiliation">, Bauhaus University, Weimar</span></div> <div class="author"><span class="authorName">Stefan Lucks</span><a class="ms-1" target="_blank" href="https://orcid.org/0000-0003-4906-5131"><img class="align-baseline orcidIcon" src="/img/orcid.svg"></a><span class="affiliation">, Bauhaus University, Weimar</span></div> <div class="author"><span class="authorName">Bart Mennink</span><a class="ms-1" target="_blank" href="https://orcid.org/0000-0001-6679-1878"><img class="align-baseline orcidIcon" src="/img/orcid.svg"></a><span class="affiliation">, Radboud University Nijmegen</span></div> <div class="author"><span class="authorName">Suprita Talnikar</span><a class="ms-1" target="_blank" href="https://orcid.org/0000-0002-9295-6688"><img class="align-baseline orcidIcon" src="/img/orcid.svg"></a><span class="affiliation">, Indian Statistical Institute</span></div> <h5 class="mt-3">Abstract</h5> <p style="white-space: pre-wrap;">We examine the post-quantum security of the Ascon authenticated encryption (AE) mode. In spite of comprehensive research of Ascon's classical security, the potential impact of quantum adversaries on Ascon has not yet been explored much. We investigate the generic security of the Ascon AE mode in the setting where the adversary owns a quantum computer to improve its attack, while the adversarial encryption or decryption queries are still classical. In this so-called Q1 model, Ascon achieves security up to approximately $\min\{2^{c/3},2^{k/2}\}$ evaluations, where $c$ is the capacity, $k$ the key size, and the adversary is block-wise adaptive but restricted to one forgery attempt. Our technique is based on applying the semi-classical one-way to hiding (O2H) lemma, and on tailoring the puncture set to the Ascon mode. Additionally, we discuss different parameter choices for Ascon and compare our results to generic quantum attacks, such as Grover-based key search and state recovery.</p> </div> <div id="metadata" class="col-md-5 col-lg-4 ps-md-5 mt-4 mt-md-0"> <h5>Metadata</h5> <dl> <dt> Available format(s) </dt> <dd> <a class="btn btn-sm btn-outline-dark" href="/2025/411.pdf"> <img class="icon" src="/img/file-pdf.svg">PDF</a> </dd> <dt>Category</dt> <dd><a href="/search?category=SECRETKEY"><small class="badge category category-SECRETKEY">Secret-key cryptography</small></a></dd> <dt>Publication info</dt> <dd>Preprint. </dd> <dt>Keywords</dt> <dd class="keywords"><a href="/search?q=post-quantum%20security" class="me-2 badge bg-secondary keyword">post-quantum security</a><a href="/search?q=lightweight%20cryptography" class="me-2 badge bg-secondary keyword">lightweight cryptography</a><a href="/search?q=Ascon" class="me-2 badge bg-secondary keyword">Ascon</a><a href="/search?q=authenticated%20encryption" class="me-2 badge bg-secondary keyword">authenticated encryption</a></dd> <dt>Contact author(s)</dt> <dd><span class="font-monospace"> nathalie lang<span class="obfuscate"> @ </span>uni-weimar de<br>stefan lucks<span class="obfuscate"> @ </span>uni-weimar de<br>b mennink<span class="obfuscate"> @ </span>cs ru nl<br>suprita45<span class="obfuscate"> @ </span>gmail com </span> </dd> <dt>History</dt> <dd>2025-03-04: approved</dd> <dd>2025-03-04: received</dd> <dd><a rel="nofollow" href="/archive/versions/2025/411">See all versions</a></dd> <dt>Short URL</dt> <dd><a href="https://ia.cr/2025/411">https://ia.cr/2025/411</a></dd> <dt>License</dt> <dd><a rel="license" target="_blank" href="https://creativecommons.org/licenses/by/4.0/"> <img class="licenseImg" src="/img/license/CC_BY.svg" alt="Creative Commons Attribution" title="Creative Commons Attribution"><br> <small>CC BY</small> </a> </dd> </dl> </div> </div> <p class="mt-4"><strong>BibTeX</strong> <button id="bibcopy" class="ms-2 btn btn-sm btn-outline-dark" aria-label="Copy to clipboard" onclick="copyBibtex()"> <img src="/img/copy-outline.svg" class="icon">Copy to clipboard</button></p> <pre id="bibtex"> @misc{cryptoeprint:2025/411, author = {Nathalie Lang and Stefan Lucks and Bart Mennink and Suprita Talnikar}, title = {Security of the Ascon Authenticated Encryption Mode in the Presence of Quantum Adversaries}, howpublished = {Cryptology {ePrint} Archive, Paper 2025/411}, year = {2025}, url = {https://eprint.iacr.org/2025/411} } </pre> <script> var bibcopy; function triggerTooltip() { console.log('setting tooltip'); } window.onload = triggerTooltip; function copyBibtex() { let range = document.createRange(); range.selectNode(document.getElementById('bibtex')); window.getSelection().removeAllRanges(); window.getSelection().addRange(range); document.execCommand('copy'); window.getSelection().removeAllRanges(); let bibcopy = document.getElementById('bibcopy'); let copyTooltip = new bootstrap.Tooltip(bibcopy, {trigger: 'manual', title: 'Copied!'}); copyTooltip.show(); setTimeout(function() { copyTooltip.dispose(); }, 2000); } </script> </main> <div class="container-fluid mt-auto" id="eprintFooter"> <a href="https://iacr.org/"> <img id="iacrlogo" src="/img/iacrlogo_small.png" class="img-fluid d-block mx-auto" alt="IACR Logo"> </a> <div class="colorDiv"></div> <div class="alert alert-success w-75 mx-auto"> Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content. </div> </div> <script src="/css/bootstrap/js/bootstrap.bundle.min.js"></script> <script> var topNavbar = document.getElementById('topNavbar'); if (topNavbar) { document.addEventListener('scroll', function(e) { if (window.scrollY > 100) { topNavbar.classList.add('scrolled'); } else { topNavbar.classList.remove('scrolled'); } }) } </script> </body> </html>