CVE-2026-42771

Issue summary: When the X509_VERIFY_PARAM_set1_email is called by an<br /> application to validate a crafted e-mail address, such as during S/MIME<br /> message validation, an out of bounds read can happen.<br /> <br /> Impact summary: This out of bounds read will not directly exfiltrate<br /> the data read to the attacker so the most likely result is a crash and<br /> a Denial of Service.<br /> <br /> An internal helper function called from X509_VERIFY_PARAM_[set|add]_email()<br /> used a wrong length when validating the local part of an email address.<br /> This could cause the 64 octet limit on the local part of an email address<br /> to be not enforced, or cause an out of bound read and potentially a crash.<br /> <br /> The bug is reachable via S-MIME validation with a crafted From: address<br /> supplied in an email message that can potentially cause a crash.<br /> <br /> No FIPS modules are affected by this issue as the affected code is outside<br /> the OpenSSL FIPS module boundary.