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.

No CVSS v4.0

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact None

Integrity Impact None

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
facelessuser soupsieve affected
Version Status Constraints
< 2.8.4 affected —

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Project Subscriptions

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-2wc2-fm75-p42x Soup Sieve has Memory Exhaustion via Large Comma-Separated Selector Lists
Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/facelessuser/soupsieve/commit/28108ab805818c832d9568142a99844fd95a0d39 cve-icon
https://github.com/facelessuser/soupsieve/releases/tag/2.8.4 cve-icon
https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x cve-icon
History

Tue, 14 Jul 2026 21:15:00 +0000

Type Values Removed Values 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.
Title Soup Sieve: Memory Exhaustion via Large Comma-Separated Selector Lists in soupsieve
Weaknesses CWE-400
CWE-770
References
Metrics cvssV3_1

{'score': 7.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-07-14T20:53:12.497Z

Reserved: 2026-05-30T04:17:43.095Z

Link: CVE-2026-49476

cve-icon Vulnrichment

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cve-icon NVD

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cve-icon Redhat

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cve-icon OpenCVE Enrichment

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Weaknesses