facelessuser Soup Sieve up to 2.9 Selector Matching resource consumption

Summaryinfo

A vulnerability was found in facelessuser Soup Sieve up to 2.9. It has been rated as problematic. The impacted element is an unknown function of the component Selector Matching. Performing a manipulation results in resource consumption. This vulnerability was named CVE-2026-126192. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is advised.

Detailsinfo

A vulnerability was found in facelessuser Soup Sieve up to 2.9. It has been classified as problematic. This affects an unknown function of the component Selector Matching. The manipulation with an unknown input leads to a resource consumption vulnerability. CWE is classifying the issue as CWE-400. The product does not properly control the allocation and maintenance of a limited resource. This is going to have an impact on availability. The summary by CVE is:

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.

It is possible to read the advisory at github.com. This vulnerability is uniquely identified as CVE-2026-126192 since 11/10/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. The technical details are unknown and an exploit is not publicly available. The attack technique deployed by this issue is T1499 according to MITRE ATT&CK.

Upgrading to version 2.10 eliminates this vulnerability.

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Productinfo

Vendor

• facelessuser

Name

• Soup Sieve

Version

• 2.0
• 2.1
• 2.2
• 2.3
• 2.4
• 2.5
• 2.6
• 2.7
• 2.8
• 2.9

CPE 2.3info

• 🔒
• 🔒
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CPE 2.2info

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• 🔒
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Entryinfo

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