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CVE-2026-110863

Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providers

CVSS score

8.6

EPSS probability

%0.3

Risk score

0.0

Published

16 h ago

OverviewPublic Exploits (0)NewsroomVulnerability Timeline
Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

CVE AI research

The stored explanation is shown at once; refreshing evaluates the sources again.

DayBreach AI Explanation

Verified against sources

CVE-2026-110863: Better Auth @better-auth/sso Authentication Bypass Vulnerability

Sources read

2

Source agreement

0/2

Evidence confidence

%47

Short explanation

Better Auth @better-auth/sso contains an authentication bypass vulnerability allowing users to sign in as others via personal SSO providers.

Why does it matter?

This vulnerability allows authenticated attackers to sign in as other users due to flawed account lookup logic, leading to account compromise.

What should be done?

  • Monitor vendor security advisories
  • Update affected components
  • Review configurations based on vendor guidance
Note on uncertainty

2 alanda kaynak uyuşmazlığı var. DayBreach bu değerleri saklamadı; kaynak karşılaştırması aşağıda gösteriliyor.

Chain of evidence and sources2 verified claims

Better Auth @better-auth/sso paketinin 1.7.0-rc.2 ile 1.7.3 arasındaki sürümleri kimlik doğrulama atlatma açığı barındırmaktadır.

S0 · daybreach-canonicalS1 · cvelist

Hesap arama işlemi providerId değerini yok saydığı için saldırganlar kurban adına oturum oluşturabilmektedir.

S0 · daybreach-canonicalS1 · cvelistS2 · nvd
Show the technical text from the sources

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.

CVSS vector: 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

CWE: CWE-287

Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-110863 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1better-authsso View
Total affected vendors: 1|Products: 1

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.6CVSS V40HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/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:XNVD
8.6CVSS V4_0HIGHCVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:NCVE CNA
8.1CVSS V31HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NNVD
8.1CVSS V3_1HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:NCVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-110863 is associated with the following CWEs:

CWE-287: Improper Authentication

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-110863 weaknesses.

CAPEC-66: SQL InjectionCAPEC-126: Path TraversalCAPEC-28: OS Command Injection

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsLow
UserGerekmiyor

Official Sources and Advisories

GitHub Security Advisory (GHSA-mx9r-x6ww-qjw9)vendor-advisoryVulnCheck Advisory: Better Auth @better-auth/sso before 1.7.3 Authentication Bypass via Personal SSO Providersvendor-advisory

CVSS Vector Radar Chart

8.6 / 10
Attack VectorNetworkComplexityLowPrivilegesLowUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

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
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow privileges
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama durumu bilinmiyor

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Follow the vendor

B
better-auth logo
better-auth

Weakness Type (CWE & CAPEC)

CWE-287

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