Vulnerability Report

CVE-2026-42771

Title: Out of Bounds Read in OpenSSL X509_VERIFY_PARAM_set1_email

Memory Corruption

Proof Of Concept

No public PoC currently indexed for CVE-2026-42771.

CWE Category CWE-125

Published Date Jun 09, 2026

Modified Date Jun 16, 2026

Exploit Status Not Found

Score 6.2 CVSS v

Exploit Probability (EPSS)

0.19%

Vulnerability Summary

CVE-2026-42771: 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.

Impacted Vendors

openssl 1

hpe 1

Reference Links

https://github.com/openssl/security/commit/6cd187689f8180c1f8a3acde21f88190c4a20de7 https://openssl-library.org/news/secadv/20260609.txt

CVSS v3.1

Source Entity 134c704f-9b21-4f2e-91b3-4a467353bcc0

Severity MEDIUM

6.2

Attack Vector

LOCAL

Complexity

LOW

Privileges

N/A

Interaction

NONE

Confidentiality

N/A

Integrity

N/A

Availability

N/A

Scope

UNCHANGED

RAW VECTOR CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Associated Attack Patterns (CAPEC)

Total: Patterns