CVE-2026-110863CWE-287

CVE-2026-110863

High · published October 15, 2026

CVSS v3.1
8.1
EPSS
0%
Percentile
18.0
In the wild
Unconfirmed
What it is

Better Auth @better-auth/sso from 1.7.0-rc.2 before 1.7.3 contains an authentication bypass vulnerability that allows authenticated users to sign in as other users by registering a personal SSO provider. Attackers can copy a legitimate provider's OIDC issuer or SAML entity ID and assert a victim's subject or NameID, because account lookup ignores providerId, creating sessions for victim accounts.

The record
Technical detail
CVSS v3.1
8.1 · HIGH
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
CVSS v4.0
8.6 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
EPSS
0.00269 · 18.0th percentile
Weakness
CWE-287 · Improper Authentication
Published
2026-10-15T03:17Z
References (2)
https://github.com/better-auth/better-auth/security/advisories/GHSA-mx9r-x6ww-qjw9 · [email protected]https://www.vulncheck.com/advisories/better-auth-better-auth-sso-before-1.7.3-authentication-bypass-via-personal-sso-providers · [email protected]
EPSS history
Timeline
  • 16 OCT 03:27Z
    EPSS moved — → 0%
    epss
  • 14 OCT 22:52Z
    Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers
    cvelistv5
  • 14 OCT 22:52Z
    Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers
    cvelistv5