CVE-2026-40162
HIGHCVE-2026-40162 is a high-severity (CVSS 7.1) Improper Input Validation vulnerability in bugsink. O3 Security confirms whether CVE-2026-40162 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Bugsink affected by authenticated arbitrary file write in artifactbundle/assemble
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Blast Radius
bugsinkReal-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
Bugsink is a self-hosted error tracking tool. In 2.1.0, an authenticated file write vulnerability was identified in Bugsink 2.1.0 in the artifact bundle assembly flow. A user with a valid authentication token could cause the application to write attacker-controlled content to a filesystem location writable by the Bugsink process. This vulnerability is fixed in 2.1.1.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | bugsink | ≥ 2.1.0&&< 2.1.1 | 2.1.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for bugsink. 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.
Fix
Update bugsink to 2.1.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-40162 is resolved across your whole dependency graph.
Workarounds
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-2026-40162 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-2026-40162. 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-2026-40162 in your dependencies?
O3 detects CVE-2026-40162 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.