How severe is CVE-2021-41146?

CVE-2021-41146 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-41146?

CVE-2021-41146 affects the following packages: qutebrowser (PyPI). Ecosystems affected: PyPI.

How do I fix CVE-2021-41146?

Update qutebrowser to 2.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41146 is resolved across your whole dependency graph.

How do I detect CVE-2021-41146 in my PyPI dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for qutebrowser. 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.

How do I mitigate CVE-2021-41146 if there is no patch (or I can't update yet)?

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 does O3 Security protect against CVE-2021-41146?

O3 pinpoints whether CVE-2021-41146 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is CVE-2021-41146 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-41146 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-41146?

CVE-2021-41146 has an EPSS (Exploit Prediction Scoring System) score of 1.4%, placing it in the 70th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

When was CVE-2021-41146 published, and has it been updated?

CVE-2021-41146 was published on October 21, 2021 and was last updated on April 10, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐍 PyPI

CVE-2021-41146

HIGH

Arbitrary command execution on Windows via qutebrowserurl: URL handler

Also known asGHSA-vw27-fwjf-5qxmPYSEC-2021-382

Published

Oct 21, 2021

Updated

Apr 10, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

1.4%probability of exploitation in next 30 days

Lower Risk70th percentile+0.70%

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

1 pkg affected

🐍qutebrowser

Real-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

qutebrowser is an open source keyboard-focused browser with a minimal GUI. Starting with qutebrowser v1.7.0, the Windows installer for qutebrowser registers a qutebrowserurl: URL handler. With certain applications, opening a specially crafted qutebrowserurl:... URL can lead to execution of qutebrowser commands, which in turn allows arbitrary code execution via commands such as :spawn or :debug-pyeval. Only Windows installs where qutebrowser is registered as URL handler are affected. The issue has been fixed in qutebrowser v2.4.0. The fix also adds additional hardening for potential similar issues on Linux (by adding the new --untrusted-args flag to the .desktop file), though no such vulnerabilities are known.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐍PyPI	`qutebrowser`	≥ 1.7.0&&< 2.4.0	2.4.0

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for qutebrowser. 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 qutebrowser to 2.4.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-41146 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-2021-41146 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-2021-41146. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

qutebrowser is an open source keyboard-focused browser with a minimal GUI. Starting with qutebrowser v1.7.0, the Windows installer for qutebrowser registers a `qutebrowserurl:` URL handler. With certain applications, opening a specially crafted `qutebrowserurl:...` URL can lead to execution of qutebrowser commands, which in turn allows arbitrary code execution via commands such as `:spawn` or `:debug-pyeval`. Only Windows installs where qutebrowser is registered as URL handler are affected. The issue has been fixed in qutebrowser v2.4.0. The fix also adds additional hardening for potential sim

O3 Security · Impact-Aware SCA

Is CVE-2021-41146 in your dependencies?

O3 detects CVE-2021-41146 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

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