CVE-2026-49476

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/facelessuser/soupsieve/commit/28108ab805818c832d9568142a99844fd95a0d39	Patch
https://github.com/facelessuser/soupsieve/releases/tag/2.8.4	Release Notes
https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x	Exploit Vendor Advisory
https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:facelessuser:soup_sieve:*:*:*:*:*:beautiful_soup:*:*

History

No history.

Information

Published : 2026-07-14 21:17

Updated : 2026-07-28 15:48

NVD link : CVE-2026-49476

Mitre link : CVE-2026-49476

CVE.ORG link : CVE-2026-49476

JSON object : View

Products Affected

facelessuser

soup_sieve

CWE

CWE-400

Uncontrolled Resource Consumption

CWE-770

Allocation of Resources Without Limits or Throttling

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