CVE-2026-14456
Description
A flaw was found in OpenSSL. A remote attacker could exploit this by sending a large number of QUIC Initial packets to an OpenSSL QUIC server. This can cause the server to allocate and queue new incoming channels without limit, leading to unbounded memory growth. The excessive memory consumption can result in a Denial of Service (DoS) condition, making the QUIC listener unavailable.
Statement
Red Hat Enterprise Linux 9.8+, 10.2+, Red Hat Hardened Images, RHIVOS 2, and OpenShift 4.22 ship OpenSSL 3.5.x which includes the QUIC server implementation affected by this flaw. Earlier RHEL versions ship OpenSSL 3.2.x or below, which do not include the QUIC server feature and are not affected. The FIPS module is not affected as the QUIC implementation is outside the OpenSSL FIPS module boundary. Applications must explicitly enable the QUIC server listener to be vulnerable; simply having OpenSSL 3.5 installed does not expose the flaw.
Mitigation
Rate-limit or firewall inbound QUIC (UDP 443) traffic at the network level to reduce exposure. If QUIC server functionality is not required, disable it and use TLS over TCP instead. The upstream fix introduces a default limit of 256 pending connections, configurable via SSL_set_value_uint(3ossl).
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 7.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other)
When allocating resources without limits, an attacker could prevent other systems, applications, or processes from accessing the same type of resource. It can be easy for an attacker to consume many resources by rapidly making many requests or causing larger resources to be used than is needed.
Frequently Asked Questions
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