7.5
HIGH CVSS 3.1
CVE-2026-7768
@fastify/accepts-serializer vulnerable to Denial of Service via Unbounded Accept Header Cache Growth
Description

@fastify/accepts-serializer cached serializer-selection results keyed by the request Accept header without a size limit or eviction policy. A remote unauthenticated client could send many distinct but matching Accept header variants to make the cache grow unbounded, eventually exhausting the Node.js heap and crashing the process. Versions <= 6.0.3 are affected. Update to 6.0.4 or later, which bounds the cache via an LRU with a default size of 100 entries, configurable through the new cacheSize plugin option.

INFO

Published Date :

May 4, 2026, 8:16 p.m.

Last Modified :

May 4, 2026, 8:16 p.m.

Remotely Exploit :

No

Source :

ce714d77-add3-4f53-aff5-83d477b104bb
Affected Products

The following products are affected by CVE-2026-7768 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH ce714d77-add3-4f53-aff5-83d477b104bb
Solution
Update the package to bound the serializer cache and prevent heap exhaustion.
  • Update @fastify/accepts-serializer to version 6.0.4 or later.
  • Configure the cache size using the cacheSize option if needed.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-7768.

URL Resource
https://cna.openjsf.org/security-advisories.html
https://github.com/fastify/fastify-accepts-serializer/security/advisories/GHSA-qxhc-wx3p-2wmg
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-7768 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-7768 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-7768 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by ce714d77-add3-4f53-aff5-83d477b104bb

    May. 04, 2026

    Action Type Old Value New Value
    Added Description @fastify/accepts-serializer cached serializer-selection results keyed by the request Accept header without a size limit or eviction policy. A remote unauthenticated client could send many distinct but matching Accept header variants to make the cache grow unbounded, eventually exhausting the Node.js heap and crashing the process. Versions <= 6.0.3 are affected. Update to 6.0.4 or later, which bounds the cache via an LRU with a default size of 100 entries, configurable through the new cacheSize plugin option.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-770
    Added Reference https://cna.openjsf.org/security-advisories.html
    Added Reference https://github.com/fastify/fastify-accepts-serializer/security/advisories/GHSA-qxhc-wx3p-2wmg
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.