CVE-2026-126192
MEDIUM
MEDIUM
Priority: 0.03
BB Relevance:
73/100
Published: 2026-11-12
Modified: 2026-11-13
First seen: 2026-11-12
Status: active
Attack Surface
Network
Low Complexity
No Auth
No Interaction
CVSS Vector Breakdown
AV:
Network
AC:
Low
PR:
None
UI:
None
S:
X
AT:
Present
VC:
None
VI:
None
VA:
Low
Description
Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.10, matching a developer-authored selector that places the general sibling combinator inside :has() repeatedly scans each candidate element's following siblings when the right-hand side is absent, producing quadratic work on attacker-controlled HTML. Applications that evaluate a fixed selector such as div:has(a ~ b) over untrusted markup can have a worker occupied for minutes by a small document, while the adjacent sibling form and trusted-only document processing are not affected in the same way. This issue is fixed in version 2.10.
Affected Software (2)
| Vendor | Product | Version |
|---|---|---|
| facelessuser | soupsieve | < 2.10 |
| facelessuser | soupsieve | < 2.10 |