NULL pointer dereference in OpenSSL - CVE-2026-42764
Published: June 10, 2026
Vulnerability identifier: #VU134274
CSH Severity: Medium
CVSS v4.0: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green
CVE-ID: CVE-2026-42764
CWE-ID: CWE-476
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 NULL pointer dereference in QUIC server initial packet handling when processing an initial packet with an invalid or expired token. A remote attacker can send a crafted initial packet to cause a denial of service.
The issue is reachable only when address validation is disabled, such as when SSL_LISTENER_FLAG_NO_VALIDATE is used with SSL_new_listener().
How to mitigate CVE-2026-42764
Install security update from vendor's website.