Overview
Unrestricted Resource Consumption vulnerabilities enable attackers to exhaust CPU, memory, and I/O resources by sending large payloads or crafting requests that trigger expensive processing. In production, this can lead to service degradation, outages, and higher cloud costs as autoscaling or saturation affects nearby tenants.
In Go with Gin, these threats often manifest when handlers read user input without limits, spawn unbounded work, or perform expensive operations based on input size. Examples include reading the entire request body into memory, performing CPU-intensive processing proportional to input, or creating goroutines per request without a cap.
Attackers can overwhelm the server by crafting requests that force large memory usage or thousands of goroutines, exhausting threads, and exhausting database connections or worker pools. The effect can ripple across the entire API surface, not just a single endpoint.
Remediation combines input and resource controls: cap request bodies, bound concurrency, apply per-request timeouts, avoid unbounded goroutine creation, and add rate limiting. The following example shows a vulnerable pattern and a secure pattern to help you migrate safely.
Code Fix Example
Go (Gin) API Security Remediation
package main
import (
"io"
"net/http"
"sync"
"github.com/gin-gonic/gin"
)
func vulnerableHandler(c *gin.Context) {
// Read entire request body and spawn a goroutine per unit of input
data, _ := io.ReadAll(c.Request.Body)
n := len(data)
for i := 0; i < n; i++ {
go func(i int) {
// heavy operation simulated
}(i)
}
c.Status(http.StatusOK)
}
func fixedHandler(c *gin.Context) {
const maxBytes = 1 << 20 // 1 MB
c.Request.Body = http.MaxBytesReader(c.Writer, c.Request.Body, maxBytes)
data, err := io.ReadAll(c.Request.Body)
if err != nil {
c.AbortWithStatus(http.StatusRequestEntityTooLarge)
return
}
n := len(data)
maxWorkers := 32
jobs := make(chan int, n)
var wg sync.WaitGroup
for w := 0; w < maxWorkers; w++ {
wg.Add(1)
go func() {
defer wg.Done()
for range jobs {
// bounded work
}
}()
}
for i := 0; i < n; i++ {
jobs <- i
}
close(jobs)
wg.Wait()
c.Status(http.StatusOK)
}
func main() {
r := gin.Default()
r.POST("/vuln", vulnerableHandler)
r.POST("/fix", fixedHandler)
// Run with explicit server timeouts to further mitigate resource exhaustion
srv := &http.Server{
Addr: ":8080",
Handler: r,
ReadTimeout: 5, // seconds
WriteTimeout: 10,
IdleTimeout: 15,
}
_ = srv.ListenAndServe()
}