OpenSSL 3.5.0 < 3.5.8 Vulnerability

high Nessus Plugin ID 335167

Synopsis

The remote service is affected by a vulnerability.

Description

The version of OpenSSL installed on the remote host is prior to 3.5.8. It is, therefore, affected by a vulnerability as referenced in the 3.5.8 advisory.

- Issue summary: When an OpenSSL QUIC server (Listener SSL object) processes valid QUIC Initial packets for unknown destination connection IDs, it can allocate and queue new incoming channels without enforcing any limit. Impact summary: A remote peer that can make many Initial packets reach the server listener faster than the application accepts connections, can cause the memory allocated to store the per-channel state to grow without any limits, potentially making the QUIC listener unavailable and causing Denial of Service.
CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: The function that handles inbound QUIC packets uses Connection-Id from the packet header to find an existing connection (QUIC channel). If no existing connection is found and the packet type is INITIAL, the function treats the packet as a new connection. It allocates a new channel object and inserts it into a queue where it waits to be accepted by the local application with SSL_accept(3ossl). The memory occupied by these initial channel objects may grow without bounds if the application is not able to call SSL_accept() frequently enough to serve these inbound connection requests. The issue is present since OpenSSL 3.5 when the QUIC server implementation was added. The fix introduces a limit for pending connections. The default limit is set to 256 pending connections (waiting to be accepted by the local application). Applications may change the default by calling SSL_set_value_uint(3ossl). FIPS impact: no The FIPS module is not affected as the QUIC implementation is outside of the OpenSSL FIPS module boundary. (CVE-2026-14456)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

Solution

Upgrade to OpenSSL version 3.5.8 or later.

Plugin Details

Severity: High

ID: 335167

File Name: openssl_3_5_8.nasl

Version: 1.1

Type: Combined

Agent: windows, macosx, unix

Family: Web Servers

Published: 8/13/2026

Updated: 8/13/2026

Configuration: Enable thorough checks (optional)

Supported Sensors: Nessus Agent, Nessus

Risk Information

CVSS v2

Risk Factor: Medium

Base Score: 5

Temporal Score: 3.7

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P

CVSS Score Source: CVE-2026-14456

CVSS v3

Risk Factor: High

Base Score: 7.5

Temporal Score: 6.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Temporal Vector: CVSS:3.0/E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:openssl:openssl

Required KB Items: installed_sw/OpenSSL

Exploit Ease: No known exploits are available

Patch Publication Date: 8/13/2026

Vulnerability Publication Date: 8/13/2026

Reference Information

CVE: CVE-2026-14456

Detections

Analytics