Buffer overflow in Snowflake Libsnowflakeclient
CVE-2026-121925
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.
Vulnerability class: Buffer Overflow
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.006 (48.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 49th percentile — 48.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
The 30-day trend appears once there are two daily scores.
Affected products
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-121925?
- CVE-2026-121925 is a medium-severity vulnerability in Snowflake Libsnowflakeclient, classified under Stack-based Buffer Overflow. CVSS score: 6.6/10. Published 2026-11-04.
- How severe is CVE-2026-121925?
- Medium severity. CVSS v3 base score is 6.6 out of 10.