Fix buffer overflow in DTLS cookie generation callback#1479
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reaperhulk merged 1 commit intopyca:mainfrom Feb 18, 2026
Merged
Fix buffer overflow in DTLS cookie generation callback#1479reaperhulk merged 1 commit intopyca:mainfrom
reaperhulk merged 1 commit intopyca:mainfrom
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The cookie generate callback copied user-returned bytes into a fixed-size native buffer without enforcing a maximum length. A callback returning more than DTLS1_COOKIE_LENGTH bytes would overflow the OpenSSL-provided buffer, corrupting adjacent memory. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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reaperhulk
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Feb 18, 2026
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The cookie generate callback copied user-returned bytes into a fixed-size native buffer without enforcing a maximum length. A callback returning more than DTLS1_COOKIE_LENGTH bytes would overflow the OpenSSL-provided buffer, corrupting adjacent memory.