CVE-2026-126193
Soup Sieve: Uncontrolled recursion in Soup Sieve CSS parser lets nested pseudo-class selectors exhaust the Python call stack
Description
Soup Sieve is a CSS selector library for Beautiful Soup. From 0.4 until 3.0, deeply nested CSS pseudo-class selectors can cause recursive parsing to exceed Python’s recursion limit and raise RecursionError . Applications accepting untrusted selectors may experience failure of the affected request or task if the exception is not handled. The demonstrated behavior is recoverable and does not establish an interpreter crash or persistent service-wide denial of service. This vulnerability is fixed in version 3.0.
INFO
Published Date :
Nov. 12, 2026, 5:17 p.m.
Last Modified :
Nov. 12, 2026, 5:17 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-126193
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | [email protected] |
Solution
- Update Soup Sieve to version 3.0 or later.
- Handle potential RecursionError exceptions gracefully.
- Validate untrusted CSS selectors before processing.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-126193.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-126193 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-126193
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-126193 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-126193 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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New CVE Received by [email protected]
Nov. 12, 2026
Action Type Old Value New Value Added Description Soup Sieve is a CSS selector library for Beautiful Soup. From 0.4 until 3.0, deeply nested CSS pseudo-class selectors can cause recursive parsing to exceed Python’s recursion limit and raise RecursionError . Applications accepting untrusted selectors may experience failure of the affected request or task if the exception is not handled. The demonstrated behavior is recoverable and does not establish an interpreter crash or persistent service-wide denial of service. This vulnerability is fixed in version 3.0. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Added CWE CWE-674 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/126xxx/CVE-2026-126193.json">CVE-2026-126193</a> Added Reference https://github.com/facelessuser/soupsieve/commit/52de12f157a373614ad0f486d434551c5a4378ee Added Reference https://github.com/facelessuser/soupsieve/pull/306 Added Reference https://github.com/facelessuser/soupsieve/releases/tag/3.0 Added Reference https://github.com/facelessuser/soupsieve/security/advisories/GHSA-7g44-g9rc-x53w