How severe is CVE-2025-53535?

No CVSS score has been assigned to CVE-2025-53535 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2025-53535?

CVE-2025-53535 affects the following packages: better-auth (npm). Ecosystems affected: npm.

How do I fix CVE-2025-53535?

Update better-auth to 1.2.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-53535 is resolved across your whole dependency graph.

How do I detect CVE-2025-53535 in my npm dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for better-auth, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2025-53535 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against CVE-2025-53535?

O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-53535 can be triaged on real exposure rather than presence alone.

Is CVE-2025-53535 actively exploited in the wild?

No public exploit code has been indexed for CVE-2025-53535 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2025-53535?

CVE-2025-53535 has an EPSS (Exploit Prediction Scoring System) score of 0.3%, placing it in the 27th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2025-53535?

CVE-2025-53535 is classified as Open Redirect (CWE-601). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was CVE-2025-53535 published, and has it been updated?

CVE-2025-53535 was published on July 7, 2025 and was last updated on August 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

📦 npm

Not in CISA KEV

CVE-2025-53535 — better-auth

Fix: better-auth/better-auth@9801d1b

CVE-2025-53535 is a Open Redirect vulnerability in better-auth. A fix is available for better-auth — see the affected versions and patch details below.

Better Auth has an Open Redirect Vulnerability in originCheck Middleware Affecting Multiple Routes

Also known asGHSA-36rg-gfq2-3h56

Published

Jul 7, 2025

Updated

Aug 12, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Sep 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.

Exploitation and automatability from CISA’s SSVC triage for CVE-2025-53535.

EPSS Exploitation Probability

via FIRST.org ↗

0.3%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs27th percentile — riskier than 27% of all scored CVEsHighest risk

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Real-World Exposure

1 pkg affected

How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.

776other npm packages depend on this — each one inherits the vulnerability until it's patched upstream

better-authnpm

6.1Mdownloads / week

Description

Summary

An open redirect has been found in the originCheck middleware function, which affects the following routes: /verify-email, /reset-password/:token, /delete-user/callback, /magic-link/verify, /oauth-proxy-callback.

Details

In the matchesPattern function, url.startsWith( can be deceived with a url that starts with one of the trustedOrigins.

		const matchesPattern = (url: string, pattern: string): boolean => {
			if (url.startsWith("/")) {
				return false;
			}
			if (pattern.includes("*")) {
				return wildcardMatch(pattern)(getHost(url));
			}
			return url.startsWith(pattern);
		};

Open Redirect PoCs

export const auth = betterAuth({
	baseURL: 'http://localhost:3000',
	trustedOrigins: [
		"http://trusted.com"
	],
	emailAndPassword: {
		...
	},
})

`/reset-password/:token`

`/verify-email`

`/delete-user/callback`

`/magic-link/verify`

`/oauth-proxy-callback`

Impact

Untrusted open redirects in various routes.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
📦npm	`better-auth`	all versions	1.2.10`npm install better-auth@1.2.10`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for better-auth, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update better-auth to 1.2.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-53535 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2025-53535 can be triaged on real exposure rather than presence alone.

Tailored to CVE-2025-53535. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary An open redirect has been found in the `originCheck` middleware function, which affects the following routes: `/verify-email`, `/reset-password/:token`, `/delete-user/callback`, `/magic-link/verify`, `/oauth-proxy-callback`. ### Details In the `matchesPattern` function, `url.startsWith(` can be deceived with a `url` that starts with one of the `trustedOrigins`. ```jsx const matchesPattern = (url: string, pattern: string): boolean => { if (url.startsWith("/")) { return false; } if (pattern.includes("*")) { return wildcardMatch(pattern)(getHost(url)); } r

O3 Security · Impact-Aware SCA

Is CVE-2025-53535 in your dependencies?

O3 Security finds CVE-2025-53535 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.

Scan my dependencies How O3 SCA works