EUVD-2026-81690
GHSA-j934-xhv5-fg8f
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Network-reachable via user-supplied selectors with low complexity and no auth/interaction; availability-only impact (worker/CPU exhaustion), no confidentiality or integrity effect.
Primary rating from Vendor (GitHub_M).
CVSS VectorVendor: GitHub_M
Lifecycle Timeline
5DescriptionCVE.org
Soup Sieve is a CSS selector library designed to be used with Beautiful Soup 4. Prior to 2.9, selector_iter in src/soupsieve/css_parser.py trims the raw selector with RE_WS_END, an end-anchored WSC whitespace-and-comment expression used with search(), so the regular expression engine retries a greedy scan at every starting offset. An attacker-controlled valid selector containing a long internal whitespace run, or a selector containing a long CSS comment run followed by another token, causes quadratic CPU work before tokenization. User-controlled selectors can reach the path through soupsieve.compile() and BeautifulSoup.select(), while applications using only hard-coded selectors are unaffected. This root cause is separate from the IDENTIFIER and VALUE backtracking vulnerability because the cost occurs in RE_WS_END.search during trimming rather than token matching. The resulting CPU consumption can hold the Python GIL, exhaust workers, and stall a service without causing memory corruption or code execution. The issue is fixed in version 2.9.
AnalysisAI
Algorithmic-complexity denial of service in Soup Sieve versions prior to 2.9 allows remote attackers to exhaust CPU and stall Python services by supplying a valid CSS selector containing a long internal whitespace run, or a long CSS comment run followed by another token, to soupsieve.compile() or BeautifulSoup.select(). The pre-tokenization trimming step performs quadratic work against the attacker-controlled string, and because the parsing happens in-process it can hold the GIL and starve worker threads, though there is no memory corruption or code execution and no confidentiality or integrity impact (CVSS 5.3, AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L). …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
Vulnerability AssessmentAI
| Exploitation | Exploitation requires that the application pass attacker-controlled CSS selectors into soupsieve.compile() or BeautifulSoup.select() on a vulnerable soupsieve (< 2.9); applications that use only hard-coded/static selectors are entirely unaffected, which is the primary limiting factor. … Additional conditions and limiting factors are described in the full assessment. |
| Risk Assessment | This is a moderate-severity algorithmic-complexity denial of service (CWE-400), not a memory-corruption or code-execution flaw despite the misleading 'RCE'/'Buffer Overflow' tags - the description explicitly states there is no memory corruption or code execution. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in. |
| Exploit Scenario | Full exploit scenario with step-by-step reproduction available after sign-in. |
| Remediation | Upgrade Soup Sieve to 2.9, the vendor-released patch version (https://github.com/facelessuser/soupsieve/releases/tag/2.9), and rebuild or redeploy any container or virtualenv that pins soupsieve below 2.9, including transitive pins pulled in by Beautiful Soup 4; verify with pip show soupsieve or pip index/pip freeze that 2.9 or later is installed. … Detailed patch versions, workarounds, and compensating controls in full report. |
Threat intelligence, references, and detailed analysis are available after sign-in.
Wazuh SIEM platform versions 4.4.0 through 4.9.0 contain an unsafe deserialization vulnerability in the DistributedAPI t
BentoML version 1.4.2 and earlier contains an unauthenticated remote code execution vulnerability through insecure deser
pgAdmin 4 contains critical remote code execution vulnerabilities in the Query Tool download and Cloud Deployment endpoi
The renderLocalView function in render/views.py in graphite-web in Graphite 0.9.5 through 0.9.10 uses the pickle Python
BentoML is a Python library for building online serving systems optimized for AI apps and model inference. Rated critica
OpenSSL before 0.9.8za, 1.0.0 before 1.0.0m, and 1.0.1 before 1.0.1h does not properly restrict processing of ChangeCiph
pyLoad download manager version prior to 0.5.0b3.dev77 exposes the Flask SECRET_KEY through an unauthenticated endpoint.
Langflow (a visual LLM pipeline builder) contains a critical unauthenticated code execution vulnerability (CVE-2026-3301
In Mercurial before 4.1.3, "hg serve --stdio" allows remote authenticated users to launch the Python debugger, and conse
Unauthenticated remote code execution affects Kestra OSS (the open-source event-driven orchestration platform) prior to
Unauthenticated remote code execution in Marimo ≤0.20.4 allows attackers to execute arbitrary system commands via the `/
pyLoad is the free and open-source Download Manager written in pure Python. Rated medium severity (CVSS 5.3), this vulne
Same weakness CWE-400 – Uncontrolled Resource Consumption
View allSame technique Denial Of Service
View allShare
External POC / Exploit Code
Leaving vuln.today