Denial of service of Minder Server from maliciously crafted GitHub attestations

Minder by Stacklok is an open source software supply chain security platform. Minder prior to version 0.0.51 is vulnerable to a denial-of-service (DoS) attack which could allow an attacker to crash the Minder server and deny other users access to it. The root cause of the vulnerability is that Minders sigstore verifier reads an untrusted response entirely into memory without enforcing a limit on the response body. An attacker can exploit this by making Minder make a request to an attacker-controlled endpoint which returns a response with a large body which will crash the Minder server. Specifically, the point of failure is where Minder parses the response from the GitHub attestations endpoint in `getAttestationReply`. Here, Minder makes a request to the `orgs/$owner/attestations/$checksumref` GitHub endpoint (line 285) and then parses the response into the `AttestationReply` (line 295). The way Minder parses the response on line 295 makes it prone to DoS if the response is large enough. Essentially, the response needs to be larger than the machine has available memory. Version 0.0.51 contains a patch for this issue. The content that is hosted at the `orgs/$owner/attestations/$checksumref` GitHub attestation endpoint is controlled by users including unauthenticated users to Minders threat model. However, a user will need to configure their own Minder settings to cause Minder to make Minder send a request to fetch the attestations. The user would need to know of a package whose attestations were configured in such a way that they would return a large response when fetching them. As such, the steps needed to carry out this attack would look as such: 1. The attacker adds a package to ghcr.io with attestations that can be fetched via the `orgs/$owner/attestations/$checksumref` GitHub endpoint. 2. The attacker registers on Minder and makes Minder fetch the attestations. 3. Minder fetches attestations and crashes thereby being denied of service.

CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H

不加限制或调节的资源分配

Minder 安全漏洞

Minder是一个开源平台，可帮助开发团队和开源社区构建更安全的软件，并向其他人证明他们构建的软件是安全的。 Minder 0.0.51之前版本存在安全漏洞，该漏洞源于验证程序将不受信任的响应完全读取到内存中，而没有对响应正文实施限制，容易受到拒绝服务(DoS)攻击。

N/A

N/A