Linux Distros Unpatched Vulnerability : CVE-2026-40898

medium Nessus Plugin ID 318811

Synopsis

The Linux/Unix host has one or more packages installed with a vulnerability that the vendor indicates will not be patched.

Description

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

- quic-go is an implementation of the QUIC protocol in Go. Prior to version 0.59.1, an attacker can cause excessive memory allocation in quic-go's HTTP/3 client and server implementations by sending a QPACK- encoded HEADERS frame that decodes into a large trailer field section with many unique field names and/or large values. The implementation builds an `http.Header` for the corresponding `http.Request` or `http.Response`, while only enforcing limits on the size of the QPACK-compressed HEADERS frame, not on the decoded field section. This can lead to memory exhaustion. This is very similar to CVE-2025-64702. The difference is that this issue uses HTTP trailers, rather than HTTP headers, as the attack vector. A misbehaving or malicious peer can cause a denial-of-service (DoS) attack against quic-go's HTTP/3 servers or clients by triggering excessive memory allocation, potentially leading to crashes or resource exhaustion. This affects both servers and clients due to symmetric header construction. Version 0.59.1 enforces RFC 9114 decoded field section size limits for trailers as well. It incrementally decodes QPACK entries and checks the field section size after each entry, aborting the stream if an entry causes the limit to be exceeded. (CVE-2026-40898)

Note that Nessus relies on the presence of the package as reported by the vendor.

Solution

There is no known solution at this time.

See Also

https://security-tracker.debian.org/tracker/CVE-2026-40898

Plugin Details

Severity: Medium

ID: 318811

File Name: unpatched_CVE_2026_40898.nasl

Version: 1.1

Type: Local

Agent: unix

Family: Misc.

Published: 6/5/2026

Updated: 6/5/2026

Supported Sensors: Nessus Agent, Nessus

Risk Information

VPR

Risk Factor: Low

Score: 2.9

CVSS v2

Risk Factor: Medium

Base Score: 4.3

Temporal Score: 3.7

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

CVSS Score Source: CVE-2026-40898

CVSS v3

Risk Factor: Medium

Base Score: 5.3

Temporal Score: 4.9

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

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

Vulnerability Information

CPE: cpe:/o:debian:debian_linux:11.0, p-cpe:/a:debian:debian_linux:golang-github-lucas-clemente-quic-go, cpe:/o:debian:debian_linux:14.0, cpe:/o:debian:debian_linux:12.0, cpe:/o:debian:debian_linux:13.0

Required KB Items: Host/cpu, Host/local_checks_enabled, global_settings/vendor_unpatched, Host/OS/identifier

Exploit Ease: No known exploits are available

Vulnerability Publication Date: 6/3/2026

Reference Information

CVE: CVE-2026-40898