CVE-2025-6518
CVE-2025-6518 is a CWE-791 vulnerability in pyspur. O3 Security confirms whether CVE-2025-6518 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
PySpur-Dev pyspur Jinja2 Template single_llm_call.py SingleLLMCallNode special elements used in a template engine
Real-World Exposure
pyspurReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
A vulnerability was found in PySpur-Dev pyspur up to 0.1.18. It has been classified as critical. Affected is the function SingleLLMCallNode of the file backend/pyspur/nodes/llm/single_llm_call.py of the component Jinja2 Template Handler. The manipulation of the argument user_message leads to improper neutralization of special elements used in a template engine. It is possible to launch the attack remotely. The exploit has been disclosed to the public and may be used.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | pyspur | all versions | No fix |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for pyspur. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of pyspur has shipped for CVE-2025-6518 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-6518 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-6518. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-6518 in your dependencies?
O3 detects CVE-2025-6518 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.