CVE-2026-49476

high

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.

References

https://github.com/facelessuser/soupsieve/security/advisories/GHSA-2wc2-fm75-p42x

https://github.com/facelessuser/soupsieve/releases/tag/2.8.4

https://github.com/facelessuser/soupsieve/commit/28108ab805818c832d9568142a99844fd95a0d39

Details

Source: Mitre, NVD

Published: 2026-07-14

Updated: 2026-07-28

Risk Information

CVSS v2

Base Score: 7.8

Vector: CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:C

Severity: High

CVSS v3

Base Score: 7.5

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Severity: High

EPSS

EPSS: 0.00601