Buffer overflow in Snowflake Libsnowflakeclient

CVE-2026-16870

Multiple security vulnerabilities in Snowflake libsnowflakeclient versions prior to 2.9.2 could allow remote code execution and credential exfiltration. A stack-based buffer overflow in the file download path could allow remote code execution on a victim host. An attacker could exploit this by uploading a file with a crafted encryption metadata field to a shared internal stage that a victim process later downloads, and impact would be limited to deployments where principals with different privilege levels share the same internal stage. A related out-of-bounds write in the same download path could allow memory corruption with attacker-controlled write primitives. An attacker may exploit this through a crafted initialization vector metadata field on a shared stage, and impact would be limited by the same stage-write precondition. Improper validation of connection parameters could allow an attacker-controlled input to redirect outbound authentication requests — including credentials and tokens — to an attacker-controlled endpoint. Impact is limited to embedding deployments where a lower-privileged principal can influence connection configuration while higher-privileged service credentials are in use. The fix is available in Snowflake libsnowflakeclient version 2.9.2. The Snowflake PHP PDO Driver and Snowflake ODBC Driver embed the affected library; fixes are available in versions 4.1.0 and 3.19.0 respectively. Users must manually upgrade.

Vulnerability class: Buffer Overflow

EPSS: 0.004 (29.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-16870?
CVE-2026-16870 is a high-severity vulnerability in Snowflake Libsnowflakeclient, classified under Stack-based Buffer Overflow. CVSS score: 8.8/10. Published 2026-07-24.
How severe is CVE-2026-16870?
High severity. CVSS v3 base score is 8.8 out of 10.