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

Tue, 09 Jun 2026 18:00:00 +0000

Type Values Removed Values Added
First Time appeared Openssl
Openssl openssl
Vendors & Products Openssl
Openssl openssl

Tue, 09 Jun 2026 16:30:00 +0000

Type Values Removed Values Added
Description Issue summary: When the X509_VERIFY_PARAM_set1_email is called by an application to validate a crafted e-mail address, such as during S/MIME message validation, an out of bounds read can happen. Impact summary: This out of bounds read will not directly exfiltrate the data read to the attacker so the most likely result is a crash and a Denial of Service. An internal helper function called from X509_VERIFY_PARAM_[set|add]_email() used a wrong length when validating the local part of an email address. This could cause the 64 octet limit on the local part of an email address to be not enforced, or cause an out of bound read and potentially a crash. The bug is reachable via S-MIME validation with a crafted From: address supplied in an email message that can potentially cause a crash. No FIPS modules are affected by this issue as the affected code is outside the OpenSSL FIPS module boundary.
Title Possible Out of Bounds Read in X509_VERIFY_PARAM_set1_email()
Weaknesses CWE-125
References

cve-icon MITRE

Status: PUBLISHED

Assigner: openssl

Published:

Updated: 2026-06-09T16:03:30.565Z

Reserved: 2026-04-29T09:22:27.969Z

Link: CVE-2026-42771

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-06-09T17:17:08.663

Modified: 2026-06-09T17:17:08.663

Link: CVE-2026-42771

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-06-09T17:45:10Z