CVE-2026-49477
Received
Received - Intake
BaseFortify
Vulnerability report for CVE-2026-49477, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-07-14
Last updated on: 2026-07-14
Assigner: GitHub, Inc.
Description
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 contains a regular expression vulnerable to catastrophic backtracking when processing an attribute selector with an unterminated quoted value in soupsieve/css_parser.py, allowing an attacker who can supply untrusted CSS selector strings to soupsieve.compile() or Beautiful Soup .select() / .select_one() to cause CPU exhaustion and denial of service. This issue is fixed in version 2.8.4.
CVSS Scores
EPSS Scores
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| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| whit537 | soupsieve | to 2.8.4 (exc) |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-400 | The product does not properly control the allocation and maintenance of a limited resource. |
| CWE-1333 | The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles. |
