How severe is CVE-2026-30964?

CVE-2026-30964 has a CVSS score of 5.4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2026-30964?

CVE-2026-30964 affects the following packages: web-auth/webauthn-framework (Packagist), web-auth/webauthn-lib (Packagist), web-auth/webauthn-symfony-bundle (Packagist). Ecosystems affected: Packagist.

How do I fix CVE-2026-30964?

Update web-auth/webauthn-framework to 5.2.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30964 is resolved across your whole dependency graph.

How do I detect CVE-2026-30964 in my Packagist dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for web-auth/webauthn-framework. 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-2026-30964 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-2026-30964?

O3 pinpoints whether CVE-2026-30964 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-2026-30964 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-30964 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-2026-30964?

CVE-2026-30964 has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 9th 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.

What type of vulnerability is CVE-2026-30964?

CVE-2026-30964 is classified as CWE-346 (CWE-346). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2026-30964 published, and has it been updated?

CVE-2026-30964 was published on March 10, 2026 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.

CVE-2026-30964: web-auth/webauthn-framewo… (Medium 5.4)

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk9th percentile+0.18%

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

3 pkgs affected

🐘web-auth/webauthn-framework🐘web-auth/webauthn-lib🐘web-auth/webauthn-symfony-bundle

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.

Description

web-auth/webauthn-lib is an open source set of PHP libraries and a Symfony bundle to allow developers to integrate that authentication mechanism into their web applications. Prior to 5.2.4, when allowed_origins is configured, CheckAllowedOrigins reduces URL-like values to their host component and accepts on host match alone. This makes exact origin policies impossible to express: scheme and port differences are silently ignored. This vulnerability is fixed in 5.2.4.

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
🐘Packagist	`web-auth/webauthn-framework`	≥ 5.2.0&&< 5.2.4	5.2.4
🐘Packagist	`web-auth/webauthn-lib`	≥ 5.2.0&&< 5.2.4	5.2.4
🐘Packagist	`web-auth/webauthn-symfony-bundle`	≥ 5.2.0&&< 5.2.4	5.2.4

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for web-auth/webauthn-framework. 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 web-auth/webauthn-framework to 5.2.4 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-30964 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-2026-30964 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-2026-30964. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

web-auth/webauthn-lib is an open source set of PHP libraries and a Symfony bundle to allow developers to integrate that authentication mechanism into their web applications. Prior to 5.2.4, when allowed_origins is configured, CheckAllowedOrigins reduces URL-like values to their host component and accepts on host match alone. This makes exact origin policies impossible to express: scheme and port differences are silently ignored. This vulnerability is fixed in 5.2.4.

O3 Security · Impact-Aware SCA

Is CVE-2026-30964 in your dependencies?

O3 detects CVE-2026-30964 across Packagist dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVE-2026-30964