Advisories for Golang/Github.com/Gofiber/Fiber/V3 package

Description A Cross-Site Scripting (CWE-79) vulnerability in Go Fiber allows a remote attacker to inject arbitrary HTML/JavaScript by supplying Accept: text/html on any request whose handler passes attacker-influenced data to the AutoFormat() feature. This affects github.com/gofiber/fiber/v3 (DefaultRes.AutoFormat) through version 3.1.0 and github.com/gofiber/fiber/v2 (Ctx.Format) through version 2.52.12. The developer opts into content negotiation by calling AutoFormat(), but does not opt into raw HTML emission for a particular request; Fiber chooses that …

Fiber cache middleware's default key generator uses only c.Path() and does not include the query string. As a result, requests like /?id=1 and /?id=2 can map to the same cache key and share the same cached response. This can cause response mix-up (cache poisoning-like behavior) for endpoints where response content depends on query parameters.

The use of the fiber_flash cookie can force an unbounded allocation on any server. A crafted 10-character cookie value triggers an attempt to allocate up to 85GB of memory via unvalidated msgpack deserialization. No authentication is required. Every GoFiber v3 endpoint is affected regardless of whether the application uses flash messages.

Description A Path Traversal (CWE-22) vulnerability in Fiber allows a remote attacker to bypass the static middleware sanitizer and read arbitrary files on the server file system on Windows. This affects Fiber v3 through version 3.0.0. This has been patched in Fiber v3 version 3.1.0.

A denial of service vulnerability exists in Fiber v2 and v3 that allows remote attackers to crash the application by sending requests to routes with more than 30 parameters. The vulnerability results from missing validation during route registration combined with an unbounded array write during request matching.