Description

A vulnerability was found in vvbbnn00 WARP-Clash-API up to c7bf2360073959861219b422e51ae86411051b46. This affects the function doUpdateLicenseKey. The manipulation results in race condition. The attack can be launched remotely. The attack requires a high level of complexity. The exploitability is reported as difficult. The exploit has been made public and could be used. This product does not use versioning. This is why information about affected and unaffected releases are unavailable. The vendor was contacted early about this disclosure but did not respond in any way. This vulnerability only affects products that are no longer supported by the maintainer.

Executive Summary

Technical Details

Mitigations

References

Additional Metadata

{
  "score": "5.0",
  "pubDate": "2026-09-13T10:16:55.357Z",
  "pubdate": "2026-09-13T10:16:55.357Z",
  "executiveSummary": "A race condition vulnerability has been identified in the doUpdateLicenseKey function of the vvbbnn00 WARP-Clash-API project, impacting versions up to commit c7bf2360073959861219b422e51ae86411051b46.\nThis flaw allows remote attackers to potentially exploit asynchronous processing gaps during license key updates. Although the vulnerability is characterized by a high degree of complexity and difficult exploitability, its public disclosure increases the risk profile for organizations still utilizing this unmaintained software.\nThe vulnerability originates from a lack of proper synchronization when handling concurrent requests to the update mechanism, which could lead to inconsistent states or unauthorized license manipulations.\nBecause the project lacks formal versioning and has been abandoned by the maintainer, no official patches are available. Users are strongly advised to transition away from this software to secure alternatives, as the lack of active development prevents remediation of this and future security defects.\nThe attack vector is remote, meaning that if an attacker successfully orchestrates the necessary timing conditions, they could bypass intended application logic, potentially impacting the integrity of the license management process.",
  "technicalDetails": "The vulnerability resides in the doUpdateLicenseKey function within the WARP-Clash-API codebase. The root cause is a race condition arising from the improper implementation of concurrency control or mutual exclusion mechanisms when processing updates to license keys. In environments where multiple HTTP requests are issued simultaneously, the application fails to atomize the check-and-set operations necessary to validate and persist the license key state.\nThe exploitation process requires the attacker to flood the target system with a high volume of precisely timed, concurrent requests directed at the doUpdateLicenseKey endpoint. By manipulating the sequence in which these requests are processed by the application's thread pool or asynchronous event loop, an attacker may trigger a condition where the state of the license key is updated in a non-linear or incoherent fashion. This typically occurs because the application performs a 'read-modify-write' operation without locking the underlying resource, allowing an attacker to insert a state-altering action between the read and the write phases.\nAttack flow: An attacker initiates multiple parallel requests to the vulnerable function. Due to the absence of synchronized blocks, mutexes, or atomic operations within the function, the server-side logic processes these requests in a manner that causes race-induced errors. This could potentially allow for unauthorized modifications to the license key configuration, effectively circumventing the standard update verification process.\nThe impact of a successful exploit is largely centered on the integrity of the application's configuration state. Because this product is unmaintained and lacks versioning control, the vulnerable code path remains static and exposed. The requirement for a high level of complexity and difficult exploitation suggests that the attack requires precise synchronization capabilities, possibly including the use of tools designed for race condition research to achieve the exact millisecond-level timing necessary to win the race against the application's native state management. Post-exploitation, the system may operate with an inconsistent license state, which could be leveraged to gain unauthorized functionality access or disrupt service availability."
}