CVE-2026-86600: snowflake snowflake connector for .net Confused Deputy

Vulnerability summary

CVE-2026-86600 is a high (CVSS 8.2) Confused Deputy vulnerability in snowflake snowflake connector for .net. EPSS estimates a 0.51% chance of exploitation in the next 30 days, higher than 42.3% of scored vulnerabilities.

Timeline

1. 08-09-2026
   PublishedVulnerability first disclosed.
2. 10-09-2026
   Last modifiedVulnerability information updated.

Description

In affected Snowflake drivers, WORKLOAD_IDENTITY authentication requests a cloud workload-identity token and attaches it to the login request without verifying that the configured host is a Snowflake endpoint. An attacker who can modify the connection configuration can cause the driver to mint a fresh attestation and send it to a host they control. The captured token can be replayed to Snowflake for its remaining lifetime in accounts where that workload identity is already registered. On Azure, the token audience is also taken from connection configuration. Combined with an attacker-controlled host, the driver can request a Managed Identity access token scoped to a non-Snowflake Azure resource and deliver it to the attacker. That path is the only case in which impact extends beyond Snowflake; it is bounded by the token lifetime and the managed identity’s permissions. Successful exploitation requires WORKLOAD_IDENTITY authentication on a workload that already has an ambient cloud identity. Patched driver versions restrict this authenticator to recognized Snowflake hosts. Users must manually upgrade.

• CWE-441Unintended Proxy or Intermediary ('Confused Deputy')The product receives a request, message, or directive from an upstream component, but the product does not sufficiently preserve the original source of the request before forwarding the request to an external actor that is outside of the product's control sphere. This causes the product to appear to be the source of the request, leading it to act as a proxy or other intermediary between the upstream component and the external actor.
• CWE-522Insufficiently Protected CredentialsThe product transmits or stores authentication credentials, but it uses an insecure method that is susceptible to unauthorized interception and/or retrieval.