Allocation of Resources Without Limits or Throttling Affecting joserfc package, versions [,1.3.5)[1.4.0,1.4.2)
Threat Intelligence
Snyk has a proof-of-concept or detailed explanation of how to exploit this vulnerability.
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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- published20 Nov 2025
- disclosed18 Nov 2025
- creditooliv
Introduced: 18 Nov 2025
NewCVE-2025-65015 (opens in a new tab)How to fix?
Upgrade joserfc to version 1.3.5, 1.4.2 or higher.
Overview
Affected versions of this package are vulnerable to Allocation of Resources Without Limits or Throttling via the ExceededSizeError exception. An attacker can cause excessive memory consumption and potentially disrupt service availability by sending arbitrarily large JWT tokens in HTTP request headers, which are then logged or processed by diagnostic tools.
Note: This is only exploitable if the web application does not enforce limits on HTTP header sizes and is not protected by a properly configured reverse proxy or web server.
Workaround
This vulnerability can be mitigated by configuring the underlying web server or reverse proxy to enforce strict limits on HTTP header sizes, preventing excessively large tokens from reaching the application.