CVE-2026-67334 — better-auth
CVE-2026-67334 is a CWE-459 vulnerability in better-auth. A fix is available for better-auth — see the affected versions and patch details below.
better-auth Stale Sessions Persist After User Deletion
Exploitation Status
No confirmed exploitation observed yet
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-67334.
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.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
better-authnpm@better-auth/scimnpmDescription
better-auth versions before 1.6.11 fail to delete cached sessions when removing users via admin, anonymous, or SCIM endpoints when secondaryStorage is configured and storeSessionInDatabase is false. Attackers can reuse deleted user session tokens to maintain authentication for up to seven days after account deletion.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | better-auth | ≥ 0.3.4&&< 1.6.11 | 1.6.11npm install better-auth@1.6.11 |
| 📦npm | @better-auth/scim | ≥ 1.6.0&&< 1.6.11 | 1.6.11npm install @better-auth/scim@1.6.11 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for better-auth, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update better-auth to 1.6.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-67334 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 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-67334 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-67334. 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-2026-67334 in your dependencies?
O3 Security finds CVE-2026-67334 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.