7.5
HIGH CVSS 3.1
CVE-2026-49476
Soup Sieve: Memory Exhaustion via Large Comma-Separated Selector Lists in soupsieve
Description

Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve allocates unbounded memory when compiling large comma-separated selector lists, allowing an attacker who can supply a crafted selector string to soupsieve.compile() or Beautiful Soup .select() / .select_one() to allocate hundreds of megabytes of heap memory from a relatively small input and cause denial of service. This issue is fixed in version 2.8.4.

INFO

Published Date :

July 14, 2026, 9:17 p.m.

Last Modified :

July 14, 2026, 9:17 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-49476 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 [email protected]
Solution
Update Soup Sieve to version 2.8.4 or later to fix memory allocation vulnerability.
  • Update Soup Sieve to 2.8.4 or later.
  • Review selector inputs for untrusted sources.
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-2026-49476.

URL Resource
https://github.com/facelessuser/soupsieve/commit/28108ab805818c832d9568142a99844fd95a0d39
https://github.com/facelessuser/soupsieve/releases/tag/2.8.4
https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-49476 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-2026-49476 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-49476 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]

    Jul. 14, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'facelessuser', 'product': 'soupsieve', 'versions': [{'status': 'affected', 'version': '< 2.8.4'}]}]
    Added Description Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.8.4, the CSS selector parser in soupsieve allocates unbounded memory when compiling large comma-separated selector lists, allowing an attacker who can supply a crafted selector string to soupsieve.compile() or Beautiful Soup .select() / .select_one() to allocate hundreds of megabytes of heap memory from a relatively small input and cause denial of service. This issue is fixed in version 2.8.4.
    Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-400
    Added CWE CWE-770
    Added Reference https://github.com/facelessuser/soupsieve/commit/28108ab805818c832d9568142a99844fd95a0d39
    Added Reference https://github.com/facelessuser/soupsieve/releases/tag/2.8.4
    Added Reference https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x
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.