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CVE-2026-110862

Status: DeferredCritical (9.3)—
Severity9.3Critical · CVSS 4.0
Exploitation probability0.32 %higher than 24% of CVEs
Active exploitationNonot in the CISA catalog
Public exploitNot knownno public code found

Better Auth from 1.4.0-beta.18 before 1.7.7 contains an authentication bypass vulnerability that allows unauthenticated attackers to sign in as other users by reusing OAuth state values as Magic Link tokens. Attackers can start an OAuth sign-in with a victim's email and submit the returned state to Magic Link verification, gaining sessions or creating falsely email-verified accounts.

CVSS

Base score
9.3
Version
4.0
Vector
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days
0.32 %
Percentile among all scored CVEs
24
Score date
10/20/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

Vector AV:N/PR:N/UI:N y el texto indica bypass de autenticación que permite iniciar sesión como otros usuarios reutilizando valores OAuth state como tokens Magic Link.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

ATT&CK mitigations that cover these techniques

Privileged Account ManagementApplication Developer GuidanceActive Directory ConfigurationVulnerability ScanningUser TrainingUser Account Management

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Better-auth — Better AuthAI

CWEs

References

Show 2 references

Raw JSON (NVD)

Show
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