Critical-Severity Improper Authentication Flaw in better-auth Tracked as CVE-2026-110864
A newly published critical vulnerability in better-auth carries a CVSS score of 9.1. Here is what is affected and how to respond.
Key points
- CVE-2026-110864 affects better-auth.
- CVSS 9.1 (Critical).
- No exploitation confirmed yet.
A critical improper authentication tracked as CVE-2026-110864 has been published in the National Vulnerability Database for better-auth, with a CVSS base score of 9.1.
At a glance
- CVE
- CVE-2026-110864
- Product
- better-auth
- CVSS
- 9.1 Critical
- Weakness
- improper authentication
- Exploited
- No known exploitation
What is the vulnerability?
The NVD entry states: Better Auth from 1.5.0-beta.12 before 1.7.7 contains an authentication bypass vulnerability in the OAuth Proxy plugin that allows unauthenticated attackers to sign in as other users by forging encrypted profiles. When the proxy shares the global secret and cookie-stored state is used, attackers can obtain encrypted state for a fake profile with a victim's verified email to take over the account via implicit linking.
Affected versions
| Vendor | Product | Versions |
|---|---|---|
| Better-Auth | better-auth | before 1.7.7 |
Is it being exploited?
There is no public confirmation of exploitation at the time of publication. It does not appear in CISA's Known Exploited Vulnerabilities catalog. We will update this report if that changes.
What should you do?
- Identify whether the affected product and versions run in your environment.
- Apply the vendor update listed in the advisory as soon as it is available.
- Limit network exposure of the affected service until it is patched.
- Monitor the vendor advisory for updated guidance or exploitation reports.
What to do and how to stay safe: CVE-2026-110864
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-110864?
CVE-2026-110864 is a improper authentication vulnerability in better-auth.
How severe is CVE-2026-110864?
It has a CVSS score of 9.1 Critical.
Is CVE-2026-110864 being exploited?
There is no public confirmation of exploitation at the time of publication.
