PostScript Subroutine Injection

vendor:
Ghostscript
by:
N/A
8.8
CVSS
HIGH
PostScript Subroutine Injection
CWE
Product Name: Ghostscript
Affected Version From: 9.26
Affected Version To: 9.26
Patch Exists: No
Related CWE: N/A
CPE: o:ghostscript:ghostscript
Metasploit: N/A
Other Scripts: N/A
Platforms Tested: N/A
2020
PostScript Subroutine Injection

PostScript is a programming language used to create documents for printing. It is vulnerable to subroutine injection, which is a type of attack that allows an attacker to inject malicious code into a subroutine. This can be done by changing the dictstack, which is similar to variable scope in other languages. This can allow an attacker to execute arbitrary code on the system, leading to a complete compromise.
Mitigation:

To mitigate this vulnerability, it is important to ensure that all subroutines are properly protected. This includes binding the routine, and making sure that all commands and operators are resolved at define-time.
Source
Exploit-DB raw data:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <meta name="robots" content="noindex, nofollow">
    <title>502 Hosting Server Connect Timeout | Sucuri Website Firewall</title>
    <!--
        Base origin-error page (502/504). lualibs/error_pages.lua fills the double-brace placeholders
        per $whitelabel at request time; init.lua substitutes the server id at load. Keep it
        self-contained: no external stylesheet, script, font, CSS import or remote image
        (tests/rules/71-error-pages-self-contained.sh).
    -->
    <style>
        :root {
            --accent: #3b7a26;
        }

        * {
            box-sizing: border-box;
        }

        html {
            -webkit-text-size-adjust: 100%;
        }

        body {
            margin: 0;
            background: #f4f5f7;
            color: #1d2330;
            font: 16px/1.55 -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
        }

        a {
            color: var(--accent);
        }

        p {
            margin: 0 0 10px;
        }

        .wrap {
            max-width: 760px;
            margin: 0 auto;
            padding: 32px 16px 48px;
        }

        .product {
            margin: 0 0 20px;
            font-size: 14px;
            font-weight: 600;
            letter-spacing: .02em;
            color: var(--accent);
        }

        .card {
            padding: 28px 24px;
            background: #fff;
            border: 1px solid #e1e4ea;
            border-radius: 10px;
        }

        h1 {
            margin: 0 0 6px;
            font-size: 26px;
            line-height: 1.25;
        }

        h2 {
            margin: 24px 0 8px;
            font-size: 17px;
        }

        .lead {
            margin: 0 0 4px;
            font-size: 18px;
            color: #414a5a;
        }

        .retry {
            margin: 0;
            color: #5b6475;
        }

        /* You -> Firewall -> Hosting diagram */
        .flow {
            display: flex;
            align-items: flex-start;
            justify-content: space-between;
            gap: 8px;
            margin: 28px 0;
            padding: 0;
            list-style: none;
        }

        .node {
            flex: 0 0 auto;
            width: 132px;
            text-align: center;
            font-size: 14px;
            font-weight: 600;
        }

        .icon {
            position: relative;
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 64px;
            height: 64px;
            margin-bottom: 6px;
            border-radius: 50%;
        }

        .icon svg {
            width: 32px;
            height: 32px;
            fill: none;
            stroke: currentColor;
            stroke-width: 1.8;
            stroke-linecap: round;
            stroke-linejoin: round;
        }

        .ok-node .icon {
            background: #e7f4ea;
            color: #2f7d3c;
        }

        .fail-node,
        .fail-node .icon {
            color: #c0362c;
        }

        .fail-node .icon {
            background: #fdebea;
        }

        .badge {
            position: absolute;
            right: -2px;
            bottom: -2px;
            width: 22px;
            height: 22px;
            border-radius: 50%;
            color: #fff;
            font-size: 13px;
            line-height: 22px;
        }

        .badge.ok {
            background: #2f7d3c;
        }

        .badge.fail {
            background: #c0362c;
        }

        /* Connector, vertically centred on the 64px icons */
        .link {
            flex: 1 1 auto;
            height: 2px;
            margin-top: 31px;
            background: #c9ced8;
        }

        .link.broken {
            background: repeating-linear-gradient(90deg, #c0362c 0 6px, transparent 6px 11px);
        }

        dl {
            display: grid;
            grid-template-columns: max-content 1fr;
            gap: 4px 16px;
            margin: 0;
            padding: 14px 16px;
            background: #f7f8fa;
            border-radius: 8px;
            font-size: 15px;
        }

        dt {
            color: #5b6475;
        }

        dd {
            margin: 0;
            font-weight: 600;
            overflow-wrap: anywhere;
        }

        ul.causes {
            margin: 0;
            padding-left: 20px;
        }

        footer {
            margin-top: 20px;
            font-size: 13px;
            color: #6b7383;
            text-align: center;
        }

        @media (max-width: 520px) {
            .wrap {
                padding: 20px 16px 32px;
            }

            .card {
                padding: 20px 16px;
            }

            h1 {
                font-size: 22px;
            }

            .flow {
                gap: 4px;
            }

            .node {
                flex: 1 1 0;
                width: auto;
                min-width: 0;
                font-size: 12px;
                line-height: 1.3;
            }

            /* Connector, vertically centred on the 52px icons */
            .link {
                flex: 0 0 14px;
                margin-top: 25px;
            }

            .icon {
                width: 52px;
                height: 52px;
            }

            .icon svg {
                width: 26px;
                height: 26px;
            }
        }
    </style>
</head>
<body>
    <main class="wrap">
        <p class="product">Sucuri Website Firewall</p>

        <div class="card">
            <h1>Hosting Server Connect Timeout</h1>
            <p class="lead">HTTP 502 &mdash; Unable to Connect to the Origin Server</p>
            <p class="retry">Please try again in a few minutes.</p>

            <ol class="flow" aria-label="Connection path">
                <li class="node ok-node">
                    <span class="icon">
                        <svg viewBox="0 0 24 24" aria-hidden="true">
                            <circle cx="12" cy="8" r="4"/>
                            <path d="M4 21c0-4.4 3.6-8 8-8s8 3.6 8 8"/>
                        </svg>
                        <span class="badge ok" aria-hidden="true">&#10003;</span>
                    </span><br>
                    You
                </li>
                <li class="link" aria-hidden="true"></li>
                <li class="node ok-node">
                    <span class="icon">
                        <svg viewBox="0 0 24 24" aria-hidden="true">
                            <path d="M12 2 4 5v6c0 5 3.4 9.3 8 11 4.6-1.7 8-6 8-11V5z"/>
                        </svg>
                        <span class="badge ok" aria-hidden="true">&#10003;</span>
                    </span><br>
                    Sucuri Firewall
                </li>
                <li class="link broken" aria-hidden="true"></li>
                <li class="node fail-node">
                    <span class="icon">
                        <svg viewBox="0 0 24 24" aria-hidden="true">
                            <rect x="4" y="3" width="16" height="7" rx="1.5"/>
                            <rect x="4" y="14" width="16" height="7" rx="1.5"/>
                            <path d="M8 6.5h.01M8 17.5h.01"/>
                        </svg>
                        <span class="badge fail" aria-hidden="true">&#10005;</span>
                    </span><br>
                    Hosting Timeout
                </li>
            </ol>

            <h2>Error details</h2>
            <dl>
                <dt>Error code</dt>
                <dd>HTTP 502</dd>
                <dt>Error message</dt>
                <dd>Backend or gateway connection timeout.</dd>
                <dt>Server ID</dt>
                <dd>14012</dd>
            </dl>

            <h2>What's going on?</h2>
            <ul class="causes">
                <li>The origin server might be down</li>
                <li>The Sucuri network might be blocked by the origin&#39;s firewall</li>
            </ul>

            <h2>What can I do to fix it?</h2>
            <p>
                If you are just visiting the site, wait a bit and it should be back soon.
                We apologize for the inconvenience.
            </p>
            <p>
                If you own the website, check with your hosting company that your server is up and
                running and that they have <a href="https://docs.sucuri.net/website-firewall/troubleshooting/backend-timeout-message/">our firewall IPs allowlisted</a>.
            </p>
            <p>If the problem persists, open a ticket on our <a href="https://support.sucuri.net">support page</a> and we will help you troubleshoot.</p>
        </div>

        <footer>&copy; Sucuri Inc. All rights reserved. &middot; <a href="https://sucuri.net/privacy/">Privacy Policy</a></footer>
    </main>
</body>
</html>