Minder is a software supply chain security platform. Prior to version 0.0.50, Minder engine is susceptible to a denial of service from memory exhaustion that can be triggered from maliciously created templates. Minder engine uses templating to generate strings for various use cases such as URLs, messages for pull requests, descriptions for advisories. In some cases can the user control both the template and the params for it, and in a subset of these cases, Minder reads the generated template entirely into memory. When Minders templating meets both of these conditions, an attacker is able to generate large enough templates that Minder will exhaust memory and crash. This vulnerability is fixed in 0.0.50.

Affected: Go: github.com/stacklok/minder

Minder engine is susceptible to a denial of service from memory exhaustion that can be triggered from maliciously created templates.

Minder engine uses templating to generate strings for various use cases such as URLs, messages for pull requests, descriptions for advisories. In some cases can the user control both the template and the params for it, and in a subset of these cases, Minder reads the generated template entirely into memory. When Minders templating meets both of these conditions, an attacker is able to generate large enough templates that Minder will exhaust memory and crash.

One of these places is the REST ingester:

https://github.com/stacklok/minder/blob/daccbc12e364e2d407d56b87a13f7bb24cbdb074/internal/engine/ingester/rest/rest.go#L115-L123

With control over both endpoint and `retp` on the following line:

https://github.com/stacklok/minder/blob/daccbc12e364e2d407d56b87a13f7bb24cbdb074/internal/engine/ingester/rest/rest.go#L121

… an attacker can make Minder generate a large template that Minder reads into memory on the following line by invoking `endpoint.String()`:

https://github.com/stacklok/minder/blob/daccbc12e364e2d407d56b87a13f7bb24cbdb074/internal/engine/ingester/rest/rest.go#L131

Consider this example:

```go package main

import ( "fmt" "html/template" "os" )

type EndpointTemplateParams struct { // Params are the parameters to be used in the template Params map[string]any }

func main() { retp :…