openssl / openssl/openssl

unexpected close of connection with compressed certificate

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triaged: bug
Dominant language
C
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Avg merge
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Merged PRs (30d)
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Description

When a compressed certificate is used we send the following compressed certificate message:

struct {
CertificateCompressionAlgorithm algorithm;
uint24 uncompressed_length;
opaque compressed_certificate_message<1..2^24-1>;
} CompressedCertificate;

When we have a very big compressed_certificate_message (>1,000,000 bytes) OpenSSL closes the connection unexpectedly rather than sending a bad_certificate alert.

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Research direction

Start by reproducing the compressed-certificate case with a compressed_certificate_message larger than 1,000,000 bytes, then trace OpenSSL's TLS certificate handling to find where the connection is closed. Done means the peer receives a bad_certificate alert instead of an unexpected connection close.

Written by the indexing model from the issue text.

Assessment

Tech stack
c
Domain
cryptography, security
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Needs clarification
Newbie friendliness
35/100

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