7.5
HIGH CVSS 3.1
CVE-2026-115482
lsquic HTTP/3 Header Buffer Memory Exhaustion
Description

In lsquic before 4.9.0, the HTTP/3 implementation can use an excessive amount of memory because the number of buffered header sets is not limited, as demonstrated by a QPACK amplification attack. This is related to header_out_dynamic_entry and es_max_header_list_size.

INFO

Published Date :

Oct. 22, 2026, 4:17 p.m.

Last Modified :

Oct. 22, 2026, 5:40 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-115482 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.

ID Vendor Product Action
1 Litespeedtech lsquic
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 8254265b-2729-46b6-b9e3-3dfca2d5bfca
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
Solution
Limit the number of buffered header sets to prevent excessive memory usage.
  • Update lsquic to version 4.9.0 or later.
  • Configure header_out_dynamic_entry limits.
  • Adjust es_max_header_list_size settings.
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-2026-115482.

URL Resource
https://foxio.io/blog/header-accordions-qpack-amplification-attacks-against-http-3-servers
https://github.com/litespeedtech/lsquic/compare/v4.8.2...v4.9.0
https://github.com/litespeedtech/lsquic/pull/666
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-115482 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-2026-115482 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-115482 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 [email protected]

    Oct. 22, 2026

    Action Type Old Value New Value
    Added Description In lsquic before 4.9.0, the HTTP/3 implementation can use an excessive amount of memory because the number of buffered header sets is not limited, as demonstrated by a QPACK amplification attack. This is related to header_out_dynamic_entry and es_max_header_list_size.
    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 Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/115xxx/CVE-2026-115482.json">CVE-2026-115482</a>
    Added Reference https://foxio.io/blog/header-accordions-qpack-amplification-attacks-against-http-3-servers
    Added Reference https://github.com/litespeedtech/lsquic/compare/v4.8.2...v4.9.0
    Added Reference https://github.com/litespeedtech/lsquic/pull/666
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.