NULL Pointer Dereference Affecting openssl-perl package, versions <1:3.5.5-4.el9_8


Severity

Recommended
high

Based on Red Hat Enterprise Linux security rating.

Threat Intelligence

EPSS
0.67% (47th percentile)

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  • Snyk IDSNYK-RHEL9-OPENSSLPERL-17306676
  • published11 Jun 2026
  • disclosed9 Jun 2026

Introduced: 9 Jun 2026

NewCVE-2026-42764  (opens in a new tab)
CWE-476  (opens in a new tab)

How to fix?

Upgrade RHEL:9 openssl-perl to version 1:3.5.5-4.el9_8 or higher.
This issue was patched in RHSA-2026:25239.

NVD Description

Note: Versions mentioned in the description apply only to the upstream openssl-perl package and not the openssl-perl package as distributed by RHEL. See How to fix? for RHEL:9 relevant fixed versions and status.

Issue summary: Receiving a QUIC initial packet with an invalid token may trigger a NULL pointer dereference in the OpenSSL QUIC server with address validation disabled.

Impact summary: NULL pointer dereference typically causes abnormal termination of the affected QUIC server process and a Denial of Service.

If the address validation is disabled in the OpenSSL QUIC server implementation, an attacker can crash the server by sending an initial packet with an invalid or expired token.

By default, the client address validation is enabled in the OpenSSL QUIC server implementation, which makes the default configuration not vulnerable to this issue. However if the SSL_LISTENER_FLAG_NO_VALIDATE is used with the SSL_new_listener() call, the address validation is disabled making the vulnerable code reachable.

The FIPS modules in 4.0, 3.6, 3.5, 3.4, and 3.0 are not affected by this issue, as the affected code is outside the OpenSSL FIPS module boundary.

CVSS Base Scores

version 3.1