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<a href="https://gitlab.com/wwang37">Weiqi Wang</a> created an issue: <a href="https://gitlab.com/gnutls/gnutls/-/issues/1224">#1224</a>
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<h2 dir="auto">
<a id="user-content-description-of-problem" class="anchor" href="#description-of-problem" aria-hidden="true"></a>Description of problem:</h2>
<p dir="auto">GnuTLS sends record_overflow alert for a malformed client message. However, the client message <code>\xe8\x03\x00\x00\x02\x02\x50</code> has a valid length. From my understanding:</p>
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<p>\xe8 is type</p>
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<p>\x03\x00 is version</p>
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<p>\x00\x02 is length (2 bytes)</p>
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<p>\x02\x50 has a length of 2 bytes which corresponds with the length field</p>
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<p dir="auto">Since the type is invalid, I think an unexpected_message alert is more appropriate in this case. As per <a href="https://tools.ietf.org/html/rfc5246" rel="nofollow noreferrer noopener" target="_blank">RFC 5246</a></p>
<blockquote dir="auto">
<p>record_overflow</p>
<p>A TLSCiphertext record was received that had a length more than
2^14+2048 bytes, or a record decrypted to a TLSCompressed record
with more than 2^14+1024 bytes.</p>
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<blockquote dir="auto">
<p>unexpected_message</p>
<p>An inappropriate message was received. This alert is always fatal
and should never be observed in communication between proper
implementations.</p>
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<h2 dir="auto">
<a id="user-content-version-of-gnutls-used" class="anchor" href="#version-of-gnutls-used" aria-hidden="true"></a>Version of gnutls used:</h2>
<p dir="auto">GnuTLS 3.7.0 commit <a href="https://gitlab.com/gnutls/gnutls/-/commit/7e44152fd4076afb0b64ed311fd092669e71fa1e" data-original="7e44152fd4076afb0b64ed311fd092669e71fa1e" data-link="false" data-link-reference="false" data-project="179611" data-commit="7e44152fd4076afb0b64ed311fd092669e71fa1e" data-reference-type="commit" data-container="body" data-placement="top" title="Merge branch 'wip/dueno/typo-fixes' into 'master'" class="gfm gfm-commit has-tooltip">7e44152f</a></p>
<h2 dir="auto">
<a id="user-content-distributor-of-gnutls-eg-ubuntu-fedora-rhel" class="anchor" href="#distributor-of-gnutls-eg-ubuntu-fedora-rhel" aria-hidden="true"></a>Distributor of gnutls (e.g., Ubuntu, Fedora, RHEL)</h2>
<p dir="auto">Ubuntu 18.04</p>
<h2 dir="auto">
<a id="user-content-how-reproducible" class="anchor" href="#how-reproducible" aria-hidden="true"></a>How reproducible:</h2>
<p dir="auto">Steps to Reproduce:</p>
<p dir="auto"><code>gnutls-serv --priority NORMAL:-VERS-ALL:+VERS-TLS1.2:-COMP-ALL:+COMP-NONE --x509keyfile /path/to/key.pem --x509certfile /path/to/cert.pem -p 44331 --noticket -a --http</code></p>
<p dir="auto"><code>echo -n -e "\xe8\x03\x00\x00\x02\x02\x50" | nc 127.0.0.1 44331</code></p>
<h2 dir="auto">
<a id="user-content-actual-results" class="anchor" href="#actual-results" aria-hidden="true"></a>Actual results:</h2>
<p dir="auto">Gnutls sends record_overflow alert. The capture file is attached.</p>
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<a id="user-content-expected-results" class="anchor" href="#expected-results" aria-hidden="true"></a>Expected results:</h2>
<p dir="auto">Send unexpected_message alert.</p>
<h2 dir="auto">
<a id="user-content-attachments" class="anchor" href="#attachments" aria-hidden="true"></a>Attachments:</h2>
<p dir="auto"><a href="https://gitlab.com/gnutls/gnutls/uploads/9dc498a6f7924b71ead448fc9ad4cfef/gnutls_capture.pcap" data-link="true" class="gfm">gnutls_capture.pcap</a></p>
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