Allocation of Resources Without Limits or Throttling in OpenSSL - CVE-2026-34183

Vulnerability identifier: #VU134272

CSH Severity: Medium

CVSS v4: 8.7 [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]

CVE-ID: CVE-2026-34183

CWE-ID: CWE-770

Exploitation vector: Remote access

Exploit availability: No public exploit available

The vulnerability allows a remote attacker to cause a denial of service.

The vulnerability exists due to uncontrolled memory allocation in the QUIC PATH_CHALLENGE handler when processing floods of PATH_CHALLENGE frames. A remote attacker can send a flood of PATH_CHALLENGE frames to cause a denial of service.

The issue affects applications acting as a QUIC client or server.

OpenSSL
Debian Linux
SUSE Linux Enterprise Server for SAP Applications 15
SUSE Linux Enterprise Server 15
SUSE Linux Enterprise Real Time 15
SUSE Linux Enterprise Desktop 15
Fedora
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux Server - AUS
Red Hat Enterprise Linux for x86_64 - Extended Update Support
FreeBSD
Basesystem Module
Ubuntu
OS Image for Red Hat Enterprise Linux
IBM supplied MQ Advanced container images
Operator for PostgreSQL
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
openssl (Red Hat package)
libopenssl3-32bit
libopenssl-3-fips-provider-32bit
libopenssl-3-fips-provider-32bit-debuginfo
libopenssl3-32bit-debuginfo
openssl-3
libopenssl-3-fips-provider-debuginfo
openssl-3-debuginfo
libopenssl3
libopenssl-3-devel
openssl-3-debugsource
libopenssl-3-fips-provider
libopenssl3-debuginfo
openssl3
openssl
openssl (Ubuntu package)
openssl (Debian package)
IBM Cloud Pak for Data System
IBM MQ Operator
IBM MQ for HPE NonStop
IBM MQ
IBM Cloud Pak System
LANTIME Operating System Firmware (LTOS)
EntireX

Install security update from vendor's website.

OpenSSL - addressed in versions 3.4.6, 3.5.7, 3.6.3, 4.0.1
OS Image for Red Hat Enterprise Linux - update to 5.0.3.0
IBM Cloud Pak for Data System - update to 8.10.26.07.SP3
IBM Cloud Pak System - update to 2.3.6.2
IBM MQ Operator - addressed in versions 3.2.26 SC2, 4.0.1 SC2
LANTIME Operating System Firmware (LTOS) - update to 7.10.013
IBM MQ for HPE NonStop - update to 8.1.0.41
IBM MQ - addressed in versions 9.1.0.38, 9.2.0.44, 9.3.0.42, 9.4.0.26, 10.0.0.5
IBM supplied MQ Advanced container images - update to 10.0.0.0-r2
EntireX - update to 12.1 Fix2
openssl (Red Hat package) - addressed in versions 3.2.2-7.el9_6.4, 3.2.2-16.el10_0.7, 3.5.5-4.el9_8, 3.5.5-4.el10_2
libopenssl3-32bit - update to 3.2.3-150700.5.36.1
libopenssl-3-fips-provider-32bit - update to 3.2.3-150700.5.36.1
libopenssl-3-fips-provider-32bit-debuginfo - update to 3.2.3-150700.5.36.1
libopenssl3-32bit-debuginfo - update to 3.2.3-150700.5.36.1
openssl-3 - update to 3.2.3-150700.5.36.1
libopenssl-3-fips-provider-debuginfo - update to 3.2.3-150700.5.36.1
openssl-3-debuginfo - update to 3.2.3-150700.5.36.1
libopenssl3 - update to 3.2.3-150700.5.36.1
libopenssl-3-devel - update to 3.2.3-150700.5.36.1
openssl-3-debugsource - update to 3.2.3-150700.5.36.1
libopenssl-3-fips-provider - update to 3.2.3-150700.5.36.1
libopenssl3-debuginfo - update to 3.2.3-150700.5.36.1
openssl3 - update to 3.5.5-5.el8
openssl - update to 3.5.7-1.fc44
openssl (Ubuntu package) - addressed in versions 3.0.2-0ubuntu1.25, 3.0.13-0ubuntu3.11, 3.5.3-1ubuntu3.4, 3.5.5-1ubuntu3.2
openssl (Debian package) - addressed in versions 3.0.20-1~deb12u2, 3.5.6-1~deb13u2

• https://openssl-library.org/news/secadv/20260609.txt

• Multiple vulnerabilities in OpenSSL
• Debian update for openssl
• Ubuntu update for openssl
• Fedora 44 update for openssl
• Red Hat Enterprise Linux 10 update for openssl
• Red Hat Enterprise Linux 9 update for openssl
• FreeBSd update for OpenSSL
• SUSE update for openssl-3
• Multiple vulnerabilities in IBM Operator for PostgreSQL
• Multiple vulnerabilities in IBM EntireX
• Multiple vulnerabilities in IBM MQ Operator and Queue manager container images
• Fedora EPEL 8 update for openssl3
• Multiple vulnerabilities in Meinberg LANTIME firmware
• Multiple vulnerabilities in IBM Cloud Pak for Data System
• Multiple vulnerabilities in IBM MQ
• Multiple vulnerabilities in IBM MQ for HPE NonStop
• Red Hat Enterprise Linux 10 update for openssl
• Multiple vulnerabilities in IBM Cloud Pak System
• Red Hat Enterprise Linux 9 update for openssl