CVE-2026-49477 (GCVE-0-2026-49477)

Vulnerability from cvelistv5 – Published: 2026-07-14 20:51 – Updated: 2026-07-21 14:49
VLAI
Title
Soup Sieve: Regular Expression Denial of Service (ReDoS) in soupsieve Selector Parser
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-21 14:49 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
  • CWE-1333 - Inefficient Regular Expression Complexity
Assigner
References
Impacted products
Vendor Product Version CPE status
facelessuser soupsieve Affected: < 2.8.4
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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