{"id":"CVE-2026-110861","sourceIdentifier":"disclosure@vulncheck.com","published":"2026-10-14T23:17:27.490","lastModified":"2026-10-20T03:17:14.297","vulnStatus":"Awaiting Analysis","cveTags":[],"descriptions":[{"lang":"en","value":"Better Auth @better-auth/drizzle-adapter and better-auth from 1.6.17 before 1.7.7, and @better-auth/kysely-adapter from 1.6.17 before 1.7.0, contain a race condition in database-backed rate limiting on PostgreSQL where the limit check is not atomic with the counter update. Remote attackers can send bursts of concurrent requests that pass the check together, exceeding configured limits on password sign-in, two-factor verification, one-time code, password reset, and other rate-limited endpoints."}],"affected":[{"source":"disclosure@vulncheck.com","affectedData":[{"vendor":"better-auth","product":"drizzle-adapter","defaultStatus":"unaffected","packageURL":"pkg:npm/%40better-auth/drizzle-adapter","versions":[{"version":"1.6.17","lessThan":"1.7.7","versionType":"semver","status":"affected"},{"version":"1.7.7","versionType":"semver","status":"unaffected"}]},{"vendor":"better-auth","product":"kysely-adapter","defaultStatus":"unaffected","packageURL":"pkg:npm/%40better-auth/kysely-adapter","versions":[{"version":"1.6.17","lessThan":"1.7.0","versionType":"semver","status":"affected"},{"version":"1.7.0","versionType":"semver","status":"unaffected"}]},{"vendor":"better-auth","product":"better-auth","defaultStatus":"unaffected","packageURL":"pkg:npm/better-auth","versions":[{"version":"1.6.17","lessThan":"1.7.7","versionType":"semver","status":"affected"},{"version":"1.7.7","versionType":"semver","status":"unaffected"}]}]}],"metrics":{"cvssMetricV40":[{"source":"disclosure@vulncheck.com","type":"Secondary","cvssData":{"version":"4.0","vectorString":"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/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","baseScore":6.3,"baseSeverity":"MEDIUM","attackVector":"NETWORK","attackComplexity":"HIGH","attackRequirements":"PRESENT","privilegesRequired":"NONE","userInteraction":"NONE","vulnConfidentialityImpact":"LOW","vulnIntegrityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","subIntegrityImpact":"NONE","subAvailabilityImpact":"NONE","exploitMaturity":"NOT_DEFINED","confidentialityRequirement":"NOT_DEFINED","integrityRequirement":"NOT_DEFINED","availabilityRequirement":"NOT_DEFINED","modifiedAttackVector":"NOT_DEFINED","modifiedAttackComplexity":"NOT_DEFINED","modifiedAttackRequirements":"NOT_DEFINED","modifiedPrivilegesRequired":"NOT_DEFINED","modifiedUserInteraction":"NOT_DEFINED","modifiedVulnConfidentialityImpact":"NOT_DEFINED","modifiedVulnIntegrityImpact":"NOT_DEFINED","modifiedVulnAvailabilityImpact":"NOT_DEFINED","modifiedSubConfidentialityImpact":"NOT_DEFINED","modifiedSubIntegrityImpact":"NOT_DEFINED","modifiedSubAvailabilityImpact":"NOT_DEFINED","Safety":"NOT_DEFINED","Automatable":"NOT_DEFINED","Recovery":"NOT_DEFINED","valueDensity":"NOT_DEFINED","vulnerabilityResponseEffort":"NOT_DEFINED","providerUrgency":"NOT_DEFINED"}}],"cvssMetricV31":[{"source":"disclosure@vulncheck.com","type":"Secondary","cvssData":{"version":"3.1","vectorString":"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N","baseScore":3.7,"baseSeverity":"LOW","attackVector":"NETWORK","attackComplexity":"HIGH","privilegesRequired":"NONE","userInteraction":"NONE","scope":"UNCHANGED","confidentialityImpact":"LOW","integrityImpact":"NONE","availabilityImpact":"NONE"},"exploitabilityScore":2.2,"impactScore":1.4}],"ssvcV203":[{"source":"134c704f-9b21-4f2e-91b3-4a467353bcc0","ssvcData":{"timestamp":"2026-10-20T02:26:21.724147Z","id":"CVE-2026-110861","options":[{"exploitation":"none"},{"automatable":"no"},{"technicalImpact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}]},"weaknesses":[{"source":"disclosure@vulncheck.com","type":"Secondary","description":[{"lang":"en","value":"CWE-307"}]}],"references":[{"url":"https://github.com/better-auth/better-auth/security/advisories/GHSA-44jh-23m7-hpcf","source":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/better-auth-drizzle-adapter-1.6.17-before-1.7.7-rate-limit-bypass-via-race-condition","source":"disclosure@vulncheck.com"}]}