---
id: "CVE-2026-121925"
kind: "vulnerability"
aliases: ["CVE-2026-121925"]
title: "Snowflake PHP PDO driver: SAML login overflow can crash or run code"
severity: "medium"
cvss: 6.6
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "pdo", "php", "saml", "snowflake", "sso"]
not_affected_if: ["key-pair-auth", "no-saml-login", "password-auth"]
published_at: "2026-11-04T12:17:06+00:00"
first_seen_at: "2026-11-04T12:26:52+00:00"
updated_at: "2026-11-04T12:27:39+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121925", "first_seen_at": "2026-11-04T12:26:52+00:00"}]
---

# Snowflake PHP PDO driver: SAML login overflow can crash or run code

A stack buffer overflow in libsnowflakeclient and the Snowflake PHP PDO Driver occurs when the driver copies an oversized value from the identity provider's HTML response during native SSO/SAML login. An attacker who controls or compromises the identity provider, or can redirect the SAML SSO endpoint to their own server, can crash the application or, in specific circumstances, execute code within it.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed PHP PDO driver version with `composer show snowflake/pdo` or your package manager and compare it to `4.3.0`.
- Check the libsnowflakeclient version in use against `2.11.1`.
- Look for native SSO/SAML (external browser or IdP-based) authentication in the application's Snowflake connection settings.

## Fix

- Snowflake PHP PDO Driver: `4.3.0`
- libsnowflakeclient: `2.11.1`

## Timeline

- 2026-11-04T12:26:52+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121925

## Documents

- [fix] Release notes: github.com https://github.com/snowflakedb/libsnowflakeclient/releases/tag/v2.11.1

## From the sources

A stack-based buffer overflow in libsnowflakeclient and the Snowflake PHP PDO Driver could, under specific conditions, result in memory corruption during SAML-based authentication. During a native SSO/SAML login flow, the affected drivers may have copied a value taken from the identity provider's HTML response into a fixed-size memory buffer without first validating the length of that value. An attacker who controlled or had compromised the configured identity provider — or who was able to redirect the SAML single sign-on endpoint to an attacker-controlled server — might have leveraged this by returning an oversized response, potentially resulting in a crash or, in specific circumstances, remote code execution within the context of the application running the library. The fix is available in libsnowflakeclient version 2.11.1 and Snowflake PHP PDO Driver version 4.3.0. Users must manually upgrade.

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_Free to read at a human pace. An API with keys and an MCP server are in preparation; early access: hello@infrastack.ai_