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<path d="M3.75 2h3.5a.75.75 0 0 1 0 1.5h-3.5a.25.25 0 0 0-.25.25v8.5c0 .138.112.25.25.25h8.5a.25.25 0 0 0 .25-.25v-3.5a.75.75 0 0 1 1.5 0v3.5A1.75 1.75 0 0 1 12.25 14h-8.5A1.75 1.75 0 0 1 2 12.25v-8.5C2 2.784 2.784 2 3.75 2Zm6.854-1h4.146a.25.25 0 0 1 .25.25v4.146a.25.25 0 0 1-.427.177L13.03 4.03 9.28 7.78a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042l3.75-3.75-1.543-1.543A.25.25 0 0 1 10.604 1Z"></path>
</svg>
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-link-external HeaderMenu-external-icon color-fg-subtle">
<path d="M3.75 2h3.5a.75.75 0 0 1 0 1.5h-3.5a.25.25 0 0 0-.25.25v8.5c0 .138.112.25.25.25h8.5a.25.25 0 0 0 .25-.25v-3.5a.75.75 0 0 1 1.5 0v3.5A1.75 1.75 0 0 1 12.25 14h-8.5A1.75 1.75 0 0 1 2 12.25v-8.5C2 2.784 2.784 2 3.75 2Zm6.854-1h4.146a.25.25 0 0 1 .25.25v4.146a.25.25 0 0 1-.427.177L13.03 4.03 9.28 7.78a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042l3.75-3.75-1.543-1.543A.25.25 0 0 1 10.604 1Z"></path>
</svg>
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-link-external HeaderMenu-external-icon color-fg-subtle">
<path d="M3.75 2h3.5a.75.75 0 0 1 0 1.5h-3.5a.25.25 0 0 0-.25.25v8.5c0 .138.112.25.25.25h8.5a.25.25 0 0 0 .25-.25v-3.5a.75.75 0 0 1 1.5 0v3.5A1.75 1.75 0 0 1 12.25 14h-8.5A1.75 1.75 0 0 1 2 12.25v-8.5C2 2.784 2.784 2 3.75 2Zm6.854-1h4.146a.25.25 0 0 1 .25.25v4.146a.25.25 0 0 1-.427.177L13.03 4.03 9.28 7.78a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042l3.75-3.75-1.543-1.543A.25.25 0 0 1 10.604 1Z"></path>
</svg>
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-link-external HeaderMenu-external-icon color-fg-subtle">
<path d="M3.75 2h3.5a.75.75 0 0 1 0 1.5h-3.5a.25.25 0 0 0-.25.25v8.5c0 .138.112.25.25.25h8.5a.25.25 0 0 0 .25-.25v-3.5a.75.75 0 0 1 1.5 0v3.5A1.75 1.75 0 0 1 12.25 14h-8.5A1.75 1.75 0 0 1 2 12.25v-8.5C2 2.784 2.784 2 3.75 2Zm6.854-1h4.146a.25.25 0 0 1 .25.25v4.146a.25.25 0 0 1-.427.177L13.03 4.03 9.28 7.78a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042l3.75-3.75-1.543-1.543A.25.25 0 0 1 10.604 1Z"></path>
</svg>
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-link-external HeaderMenu-external-icon color-fg-subtle">
<path d="M3.75 2h3.5a.75.75 0 0 1 0 1.5h-3.5a.25.25 0 0 0-.25.25v8.5c0 .138.112.25.25.25h8.5a.25.25 0 0 0 .25-.25v-3.5a.75.75 0 0 1 1.5 0v3.5A1.75 1.75 0 0 1 12.25 14h-8.5A1.75 1.75 0 0 1 2 12.25v-8.5C2 2.784 2.784 2 3.75 2Zm6.854-1h4.146a.25.25 0 0 1 .25.25v4.146a.25.25 0 0 1-.427.177L13.03 4.03 9.28 7.78a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042l3.75-3.75-1.543-1.543A.25.25 0 0 1 10.604 1Z"></path>
</svg>
<div class="d-lg-flex flex-items-center px-3 px-lg-0 mb-3 mb-lg-0 text-center text-lg-left">
<div class="d-lg-flex min-width-0 mb-2 mb-lg-0">
<div class="header-search flex-auto position-relative js-site-search flex-self-stretch flex-md-self-auto mb-3 mb-md-0 mr-0 mr-md-3 scoped-search site-scoped-search js-jump-to"
>
<div class="position-relative">
</option></form><form class="js-site-search-form" role="search" aria-label="Site" data-scope-type="Repository" data-scope-id="352459850" data-scoped-search-url="/K1nd4SUS/CTF-Writeups/search" data-owner-scoped-search-url="/orgs/K1nd4SUS/search" data-unscoped-search-url="/search" data-turbo="false" action="/K1nd4SUS/CTF-Writeups/search" accept-charset="UTF-8" method="get">
<label class="form-control header-search-wrapper input-sm p-0 js-chromeless-input-container header-search-wrapper-jump-to position-relative d-flex flex-justify-between flex-items-center">
<input type="text"
class="form-control js-site-search-focus header-search-input jump-to-field js-jump-to-field js-site-search-field is-clearable"
data-hotkey=s,/
name="q"
placeholder="Search"
data-unscoped-placeholder="Search GitHub"
data-scoped-placeholder="Search"
autocapitalize="off"
role="combobox"
aria-haspopup="listbox"
aria-expanded="false"
aria-autocomplete="list"
aria-controls="jump-to-results"
aria-label="Search"
data-jump-to-suggestions-path="/_graphql/GetSuggestedNavigationDestinations"
spellcheck="false"
autocomplete="off"
>
<input type="hidden" data-csrf="true" class="js-data-jump-to-suggestions-path-csrf" value="mlbuoGSmTS4NZpZ5zlOVxBmo7NUQ0mfKoXeahhh5h7Y7XWISHNlhKRS6FyNGcSadKPF6phegcZt1//1R/Woh3Q==" />
<input type="hidden" class="js-site-search-type-field" name="type" >
<svg xmlns="http://www.w3.org/2000/svg" width="22" height="20" aria-hidden="true" class="mr-1 header-search-key-slash"><path fill="none" stroke="#979A9C" opacity=".4" d="M3.5.5h12c1.7 0 3 1.3 3 3v13c0 1.7-1.3 3-3 3h-12c-1.7 0-3-1.3-3-3v-13c0-1.7 1.3-3 3-3z"></path><path fill="#979A9C" d="M11.8 6L8 15.1h-.9L10.8 6h1z"></path></svg>
<div class="Box position-absolute overflow-hidden d-none jump-to-suggestions js-jump-to-suggestions-container">
<div class="jump-to-suggestion-name js-jump-to-suggestion-name flex-auto overflow-hidden text-left no-wrap css-truncate css-truncate-target">
</div>
<div class="border rounded-2 flex-shrink-0 color-bg-subtle px-1 color-fg-muted ml-1 f6 d-none js-jump-to-badge-search">
<span>
In this repository
</span>
<span>
All GitHub
</span>
<span>↵</span>
</div>
<div aria-hidden="true" class="border rounded-2 flex-shrink-0 color-bg-subtle px-1 color-fg-muted ml-1 f6 d-none d-on-nav-focus js-jump-to-badge-jump">
Jump to
<span>↵</span>
</div>
<div class="jump-to-suggestion-name js-jump-to-suggestion-name flex-auto overflow-hidden text-left no-wrap css-truncate css-truncate-target">
</div>
<div class="border rounded-2 flex-shrink-0 color-bg-subtle px-1 color-fg-muted ml-1 f6 d-none js-jump-to-badge-search">
<span>
In this organization
</span>
<span>
All GitHub
</span>
<span>↵</span>
</div>
<div aria-hidden="true" class="border rounded-2 flex-shrink-0 color-bg-subtle px-1 color-fg-muted ml-1 f6 d-none d-on-nav-focus js-jump-to-badge-jump">
Jump to
<span>↵</span>
</div>
<div class="jump-to-suggestion-name js-jump-to-suggestion-name flex-auto overflow-hidden text-left no-wrap css-truncate css-truncate-target">
</div>
<div class="border rounded-2 flex-shrink-0 color-bg-subtle px-1 color-fg-muted ml-1 f6 d-none js-jump-to-badge-search">
<span>
In this repository
</span>
<span>
All GitHub
</span>
<span>↵</span>
</div>
<div aria-hidden="true" class="border rounded-2 flex-shrink-0 color-bg-subtle px-1 color-fg-muted ml-1 f6 d-none d-on-nav-focus js-jump-to-badge-jump">
Jump to
<span>↵</span>
</div>
</div>
</label>
</form> </div>
</div>
</div>
<div class="position-relative mr-lg-3 d-lg-inline-block">
Sign in
</div>
Sign up
</div>
</div>
</div>
</div>
</header>
</div>
<div id="start-of-content" class="show-on-focus"></div>
<div id="js-flash-container" data-turbo-replace>
<template class="js-flash-template">
<div class="flash flash-full {{ className }}">
<div class="px-2" >
<button autofocus class="flash-close js-flash-close" type="button" aria-label="Dismiss this message">
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-x">
<path d="M3.72 3.72a.75.75 0 0 1 1.06 0L8 6.94l3.22-3.22a.749.749 0 0 1 1.275.326.749.749 0 0 1-.215.734L9.06 8l3.22 3.22a.749.749 0 0 1-.326 1.275.749.749 0 0 1-.734-.215L8 9.06l-3.22 3.22a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042L6.94 8 3.72 4.78a.75.75 0 0 1 0-1.06Z"></path>
</svg>
</button>
<div aria-atomic="true" role="alert" class="js-flash-alert">
<div>{{ message }}</div>
</div>
</div>
</div>
</template>
</div>
<include-fragment class="js-notification-shelf-include-fragment" data-base-src="https://github.com/notifications/beta/shelf"></include-fragment>
<div
class="application-main "
data-commit-hovercards-enabled
data-discussion-hovercards-enabled
data-issue-and-pr-hovercards-enabled
>
<div itemscope itemtype="http://schema.org/SoftwareSourceCode" class="">
<main id="js-repo-pjax-container" >
<div id="repository-container-header" class="pt-3 hide-full-screen" style="background-color: var(--color-page-header-bg);" data-turbo-replace>
<div class="d-flex flex-wrap flex-justify-end mb-3 px-3 px-md-4 px-lg-5" style="gap: 1rem;">
<div class="flex-auto min-width-0 width-fit mr-3">
<div class=" d-flex flex-wrap flex-items-center wb-break-word f3 text-normal">
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-repo color-fg-muted mr-2">
<path d="M2 2.5A2.5 2.5 0 0 1 4.5 0h8.75a.75.75 0 0 1 .75.75v12.5a.75.75 0 0 1-.75.75h-2.5a.75.75 0 0 1 0-1.5h1.75v-2h-8a1 1 0 0 0-.714 1.7.75.75 0 1 1-1.072 1.05A2.495 2.495 0 0 1 2 11.5Zm10.5-1h-8a1 1 0 0 0-1 1v6.708A2.486 2.486 0 0 1 4.5 9h8ZM5 12.25a.25.25 0 0 1 .25-.25h3.5a.25.25 0 0 1 .25.25v3.25a.25.25 0 0 1-.4.2l-1.45-1.087a.249.249 0 0 0-.3 0L5.4 15.7a.25.25 0 0 1-.4-.2Z"></path>
</svg>
<span>
K1nd4SUS
</span>
<span>/</span>
CTF-Writeups
<span></span><span>Public</span>
</div>
</div>
</div>
<div id="responsive-meta-container" data-turbo-replace>
</div>
<nav data-pjax="#js-repo-pjax-container" aria-label="Repository" data-view-component="true" class="js-repo-nav js-sidenav-container-pjax js-responsive-underlinenav overflow-hidden UnderlineNav px-3 px-md-4 px-lg-5">
</div>
<turbo-frame id="repo-content-turbo-frame" target="_top" data-turbo-action="advance" class="">
<div id="repo-content-pjax-container" class="repository-content " >
<div class="clearfix container-xl px-3 px-md-4 px-lg-5 mt-4">
<div >
<div class="file-navigation mb-3 d-flex flex-items-start">
<div class="position-relative">
<details
class="js-branch-select-menu details-reset details-overlay mr-0 mb-0 "
id="branch-select-menu"
data-hydro-click-payload="{"event_type":"repository.click","payload":{"target":"REFS_SELECTOR_MENU","repository_id":352459850,"originating_url":"https://github.com/K1nd4SUS/CTF-Writeups/tree/main/X-MAS_CTF_2021/Super%20Secret%20Communications","user_id":null}}" data-hydro-click-hmac="d1e18bb6a897e6ec999f8bf1efc4068f2c65c1c45c0a2deb6c4388f553700c6f">
<summary class="btn css-truncate"
data-hotkey="w"
title="Switch branches or tags">
<svg text="gray" aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-git-branch">
<path d="M9.5 3.25a2.25 2.25 0 1 1 3 2.122V6A2.5 2.5 0 0 1 10 8.5H6a1 1 0 0 0-1 1v1.128a2.251 2.251 0 1 1-1.5 0V5.372a2.25 2.25 0 1 1 1.5 0v1.836A2.493 2.493 0 0 1 6 7h4a1 1 0 0 0 1-1v-.628A2.25 2.25 0 0 1 9.5 3.25Zm-6 0a.75.75 0 1 0 1.5 0 .75.75 0 0 0-1.5 0Zm8.25-.75a.75.75 0 1 0 0 1.5.75.75 0 0 0 0-1.5ZM4.25 12a.75.75 0 1 0 0 1.5.75.75 0 0 0 0-1.5Z"></path>
</svg>
<span>main</span>
<span></span>
</summary>
<div class="SelectMenu">
<div class="SelectMenu-modal">
<header class="SelectMenu-header">
<span>Switch branches/tags</span>
<button class="SelectMenu-closeButton" type="button" data-toggle-for="branch-select-menu"><svg aria-label="Close menu" aria-hidden="false" role="img" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-x">
<path d="M3.72 3.72a.75.75 0 0 1 1.06 0L8 6.94l3.22-3.22a.749.749 0 0 1 1.275.326.749.749 0 0 1-.215.734L9.06 8l3.22 3.22a.749.749 0 0 1-.326 1.275.749.749 0 0 1-.734-.215L8 9.06l-3.22 3.22a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042L6.94 8 3.72 4.78a.75.75 0 0 1 0-1.06Z"></path>
</svg></button>
</header>
<input-demux data-action="tab-container-change:input-demux#storeInput tab-container-changed:input-demux#updateInput">
<tab-container class="d-flex flex-column js-branches-tags-tabs" style="min-height: 0;">
<div class="SelectMenu-filter">
<input data-target="input-demux.source"
id="context-commitish-filter-field"
class="SelectMenu-input form-control"
aria-owns="ref-list-branches"
data-controls-ref-menu-id="ref-list-branches"
autofocus
autocomplete="off"
aria-label="Filter branches/tags"
placeholder="Filter branches/tags"
type="text"
>
</div>
<div class="SelectMenu-tabs" role="tablist" data-target="input-demux.control" >
<button class="SelectMenu-tab" type="button" role="tab" aria-selected="true">Branches</button>
<button class="SelectMenu-tab" type="button" role="tab">Tags</button>
</div>
<div role="tabpanel" id="ref-list-branches" data-filter-placeholder="Filter branches/tags" tabindex="" class="d-flex flex-column flex-auto overflow-auto">
<ref-selector
type="branch"
data-targets="input-demux.sinks"
data-action="
input-entered:ref-selector#inputEntered
tab-selected:ref-selector#tabSelected
focus-list:ref-selector#focusFirstListMember
"
query-endpoint="/K1nd4SUS/CTF-Writeups/refs"
cache-key="v0:1635795000.439816"
current-committish="bWFpbg=="
default-branch="bWFpbg=="
name-with-owner="SzFuZDRTVVMvQ1RGLVdyaXRldXBz"
prefetch-on-mouseover
>
<template data-target="ref-selector.fetchFailedTemplate">
<div class="SelectMenu-message" data-index="{{ index }}">Could not load branches</div>
</template>
<template data-target="ref-selector.noMatchTemplate">
<div class="SelectMenu-message">Nothing to show</div>
</template>
<div data-target="ref-selector.listContainer" role="menu" class="SelectMenu-list " data-turbo-frame="repo-content-turbo-frame">
<div class="SelectMenu-loading pt-3 pb-0 overflow-hidden" aria-label="Menu is loading">
<svg style="box-sizing: content-box; color: var(--color-icon-primary);" width="32" height="32" viewBox="0 0 16 16" fill="none" data-view-component="true" class="anim-rotate">
<circle cx="8" cy="8" r="7" stroke="currentColor" stroke-opacity="0.25" stroke-width="2" vector-effect="non-scaling-stroke" />
<path d="M15 8a7.002 7.002 0 00-7-7" stroke="currentColor" stroke-width="2" stroke-linecap="round" vector-effect="non-scaling-stroke" />
</svg>
</div>
</div>
<template data-target="ref-selector.itemTemplate">
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-check SelectMenu-icon SelectMenu-icon--check">
<path d="M13.78 4.22a.75.75 0 0 1 0 1.06l-7.25 7.25a.75.75 0 0 1-1.06 0L2.22 9.28a.751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018L6 10.94l6.72-6.72a.75.75 0 0 1 1.06 0Z"></path>
</svg>
<span>{{ refName }}</span>
<span>default</span>
</template>
<footer class="SelectMenu-footer">View all branches</footer>
</ref-selector>
</div>
<div role="tabpanel" id="tags-menu" data-filter-placeholder="Find a tag" tabindex="" hidden class="d-flex flex-column flex-auto overflow-auto">
<ref-selector
type="tag"
data-action="
input-entered:ref-selector#inputEntered
tab-selected:ref-selector#tabSelected
focus-list:ref-selector#focusFirstListMember
"
data-targets="input-demux.sinks"
query-endpoint="/K1nd4SUS/CTF-Writeups/refs"
cache-key="v0:1635795000.439816"
current-committish="bWFpbg=="
default-branch="bWFpbg=="
name-with-owner="SzFuZDRTVVMvQ1RGLVdyaXRldXBz"
>
<template data-target="ref-selector.fetchFailedTemplate">
<div class="SelectMenu-message" data-index="{{ index }}">Could not load tags</div>
</template>
<template data-target="ref-selector.noMatchTemplate">
<div class="SelectMenu-message" data-index="{{ index }}">Nothing to show</div>
</template>
<template data-target="ref-selector.itemTemplate">
<svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-check SelectMenu-icon SelectMenu-icon--check">
<path d="M13.78 4.22a.75.75 0 0 1 0 1.06l-7.25 7.25a.75.75 0 0 1-1.06 0L2.22 9.28a.751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018L6 10.94l6.72-6.72a.75.75 0 0 1 1.06 0Z"></path>
</svg>
<span>{{ refName }}</span>
<span>default</span>
</template>
<div data-target="ref-selector.listContainer" role="menu" class="SelectMenu-list" data-turbo-frame="repo-content-turbo-frame">
<div class="SelectMenu-loading pt-3 pb-0 overflow-hidden" aria-label="Menu is loading">
<svg style="box-sizing: content-box; color: var(--color-icon-primary);" width="32" height="32" viewBox="0 0 16 16" fill="none" data-view-component="true" class="anim-rotate">
<circle cx="8" cy="8" r="7" stroke="currentColor" stroke-opacity="0.25" stroke-width="2" vector-effect="non-scaling-stroke" />
<path d="M15 8a7.002 7.002 0 00-7-7" stroke="currentColor" stroke-width="2" stroke-linecap="round" vector-effect="non-scaling-stroke" />
</svg>
</div>
</div>
<footer class="SelectMenu-footer">View all tags</footer>
</ref-selector>
</div>
</tab-container>
</input-demux>
</div>
</div>
</details>
</div>
<div class="Overlay--hidden Overlay-backdrop--center" data-modal-dialog-overlay>
<modal-dialog role="dialog" id="warn-tag-match-create-branch-dialog" aria-modal="true" aria-labelledby="warn-tag-match-create-branch-dialog-header" data-view-component="true" class="Overlay Overlay--width-large Overlay--height-auto Overlay--motion-scaleFade">
<header class="Overlay-header Overlay-header--large Overlay-header--divided">
<div class="Overlay-headerContentWrap">
<div class="Overlay-titleWrap">
<h1 id="warn-tag-match-create-branch-dialog-header" class="Overlay-title">Name already in use</h1>
</div>
<div class="Overlay-actionWrap">
<button data-close-dialog-id="warn-tag-match-create-branch-dialog" aria-label="Close" type="button" data-view-component="true" class="close-button Overlay-closeButton"><svg aria-hidden="true" height="16" viewBox="0 0 16 16" version="1.1" width="16" data-view-component="true" class="octicon octicon-x">
<path d="M3.72 3.72a.75.75 0 0 1 1.06 0L8 6.94l3.22-3.22a.749.749 0 0 1 1.275.326.749.749 0 0 1-.215.734L9.06 8l3.22 3.22a.749.749 0 0 1-.326 1.275.749.749 0 0 1-.734-.215L8 9.06l-3.22 3.22a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042L6.94 8 3.72 4.78a.75.75 0 0 1 0-1.06Z"></path>
</svg></button>
</div>
</div>
</header>
<div class="Overlay-body ">
<div data-view-component="true"> A tag already exists with the provided branch name. Many Git commands accept both tag and branch names, so creating this branch may cause unexpected behavior. Are you sure you want to create this branch?
</div>
</div>
<footer class="Overlay-footer Overlay-footer--alignEnd">
<button data-close-dialog-id="warn-tag-match-create-branch-dialog" type="button" data-view-component="true" class="btn"> Cancel
</button>
<button data-submit-dialog-id="warn-tag-match-create-branch-dialog" type="button" data-view-component="true" class="btn-danger btn"> Create
</button>
</footer>
</modal-dialog></div>
<div class="flex-1 mx-2 flex-self-center f4">
<div class="d-none d-sm-block">
<span><span><span>CTF-Writeups</span></span></span><span>/</span><span><span>X-MAS_CTF_2021</span></span><span>/</span>Super Secret Communications<span>/</span>
</div>
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Super Secret Communications
Description
Solution
FLAG >>X-MAS{y0u_cr4CK4d_thE_c0d3!_afa03819def2f}
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README.MD
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<article class="markdown-body entry-content container-lg" itemprop="text"><h1 tabindex="-1" dir="auto"><svg class="octicon octicon-link" viewBox="0 0 16 16" version="1.1" width="16" height="16" aria-hidden="true"><path d="m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z"></path></svg>Super Secret Communications</h1>
<h2 tabindex="-1" dir="auto"><svg class="octicon octicon-link" viewBox="0 0 16 16" version="1.1" width="16" height="16" aria-hidden="true"><path d="m7.775 3.275 1.25-1.25a3.5 3.5 0 1 1 4.95 4.95l-2.5 2.5a3.5 3.5 0 0 1-4.95 0 .751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018 1.998 1.998 0 0 0 2.83 0l2.5-2.5a2.002 2.002 0 0 0-2.83-2.83l-1.25 1.25a.751.751 0 0 1-1.042-.018.751.751 0 0 1-.018-1.042Zm-4.69 9.64a1.998 1.998 0 0 0 2.83 0l1.25-1.25a.751.751 0 0 1 1.042.018.751.751 0 0 1 .018 1.042l-1.25 1.25a3.5 3.5 0 1 1-4.95-4.95l2.5-2.5a3.5 3.5 0 0 1 4.95 0 .751.751 0 0 1-.018 1.042.751.751 0 0 1-1.042.018 1.998 1.998 0 0 0-2.83 0l-2.5 2.5a1.998 1.998 0 0 0 0 2.83Z"></path></svg>Description</h2>
Okay, the note's right here. Hold on... uh... Okay.
You'll never discover our secrets! Our method is so secure you'll never get in! We've even given you a full packet capture of everything we sent! Do your worst, ELVES!
Yeah, we don't know either. Just try to find the secret message.
For this challenge we receive a .pcap file. Here, we find a unique TCP stream, but, by looking at the ASCII content, we would not find anything in this stream. Because of this, we need to switch to raw view. We'll see this stream of data:
By using Cyberchef, we can simply upload all the content of the stream and convert it from Hex. Here, by just scrolling a little bit, we'll find this kind of communication:
Now we could just rebuild the flag, putting together the hint and the user input.
X-MAS{y0u_cr4CK4d_thE_c0d3!_afa03819def2f}
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<path d="M13.78 4.22a.75.75 0 0 1 0 1.06l-7.25 7.25a.75.75 0 0 1-1.06 0L2.22 9.28a.751.751 0 0 1 .018-1.042.751.751 0 0 1 1.042-.018L6 10.94l6.72-6.72a.75.75 0 0 1 1.06 0Z"></path>
</svg>
</clipboard-copy>
</div>
</template>
</div>
<div id="js-global-screen-reader-notice" class="sr-only" aria-live="polite" ></div>
</body>
</html>