CVE-2025-55008Network attack vector

Session-secret disclosure via loader data serialization

Published Aug 9, 2025 · Updated Aug 11, 2025

Information exposure in WorkOS AuthKit React Router before 0.7.0 allows remote authenticated users to obtain session secrets from browser HTML. The authkitLoader returned sealedSession and accessToken in serialized loader data, causing React Router to embed both artifacts in rendered HTML. Exploitation requires access to an authenticated browser context through XSS, a malicious extension, or local inspection and enables session hijacking.

CVSS severity7.1
High
EPSS probability0.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Information exposure in WorkOS AuthKit React Router before 0.7.0 allows remote authenticated users to obtain session secrets from browser HTML. The authkitLoader returned sealedSession and accessToken in serialized loader data, causing React Router to embed both artifacts in rendered HTML. Exploitation requires access to an authenticated browser context through XSS, a malicious extension, or local inspection and enables session hijacking.

The record

CVE
CVE-2025-55008
Published
Aug 9, 2025
Updated
Aug 11, 2025
Vendor
WorkOS
Product
AuthKit React Router
Classifications
CWE-200, T1528
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Aug 9, 2025CVE publishedPublication date reported by the CVE source.
  2. Aug 11, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.7.0

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

WorkOS · AuthKit React Routerversion=< 0.7.0

Published CVSS scores

7.1GitHubCVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1528Steal Application Access Token

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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