Fiber is an Express inspired web framework written in Go. In versions 2.52.8 and below, when using Fiber's Ctx.BodyParser to parse form data containing a large numeric key that represents a slice index (e.g., test.18446744073704), the application crashes due to an out-of-bounds slice allocation in the underlying schema decoder. The root cause is that the decoder attempts to allocate a slice of length idx + 1 without validating whether the index is within a safe or reasonable range. If the idx is excessively large, this leads to an integer overflow or memory exhaustion, causing a panic or crash. This is fixed in version 2.52.9.
CVSS Score
7.5
EPSS Score
0.001
Published
2025-08-06
Fiber is an Express-inspired web framework written in Go. Starting in version 2.52.6 and prior to version 2.52.7, `fiber.Ctx.BodyParser` can map flat data to nested slices using `key[idx]value` syntax, but when idx is negative, it causes a panic instead of returning an error stating it cannot process the data. Since this data is user-provided, this could lead to denial of service for anyone relying on this `fiber.Ctx.BodyParser` functionality. Version 2.52.7 fixes the issue.
CVSS Score
7.5
EPSS Score
0.002
Published
2025-05-22
Fiber is an Express-inspired web framework written in Go A vulnerability present in versions prior to 2.52.5 is a session middleware issue in GoFiber versions 2 and above. This vulnerability allows users to supply their own session_id value, resulting in the creation of a session with that key. If a website relies on the mere presence of a session for security purposes, this can lead to significant security risks, including unauthorized access and session fixation attacks. All users utilizing GoFiber's session middleware in the affected versions are impacted. The issue has been addressed in version 2.52.5. Users are strongly encouraged to upgrade to version 2.52.5 or higher to mitigate this vulnerability. Users who are unable to upgrade immediately can apply the following workarounds to reduce the risk: Either implement additional validation to ensure session IDs are not supplied by the user and are securely generated by the server, or regularly rotate session IDs and enforce strict session expiration policies.
CVSS Score
10.0
EPSS Score
0.003
Published
2024-07-01
Fiber is a web framework written in go. Prior to version 2.52.1, the CORS middleware allows for insecure configurations that could potentially expose the application to multiple CORS-related vulnerabilities. Specifically, it allows setting the Access-Control-Allow-Origin header to a wildcard (`*`) while also having the Access-Control-Allow-Credentials set to true, which goes against recommended security best practices. The impact of this misconfiguration is high as it can lead to unauthorized access to sensitive user data and expose the system to various types of attacks listed in the PortSwigger article linked in the references. Version 2.52.1 contains a patch for this issue. As a workaround, users may manually validate the CORS configurations in their implementation to ensure that they do not allow a wildcard origin when credentials are enabled. The browser fetch api, as well as browsers and utilities that enforce CORS policies, are not affected by this.
CVSS Score
9.4
EPSS Score
0.004
Published
2024-02-21