Out-of-bounds read in OpenSSL - CVE-2026-42771
Published: June 10, 2026
Vulnerability identifier: #VU134286
CSH Severity: Low
CVSS v4.0: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear
CVE-ID: CVE-2026-42771
CWE-ID: CWE-125
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vendor: OpenSSL Software Foundation
Affected software:
OpenSSL
OpenSSL
Detailed vulnerability description
The vulnerability allows a remote attacker to cause a denial of service.
The vulnerability exists due to out-of-bounds read in X509_VERIFY_PARAM_set1_email() when validating a crafted email address. A remote attacker can supply a crafted email address to cause a denial of service.
The bug is reachable via S/MIME validation with a crafted From: address.
How to mitigate CVE-2026-42771
Install security update from vendor's website.