Security Digest · Vulnerability record
CVE-2026-15925: Snowflake Connector for Python improperly verifies TLS hostnames
Improper TLS hostname verification in Snowflake Connector for Python versions prior to 4.7.1 and 3.18.1 may have allowed a network-positioned attacker to bypass certificate hostname validation on HTTPS connections made by the connector.
CVSS 9.2 Critical EPSS 0.3% · p20
Should you act?
Critical and remotely reachable
No known exploitation yet, but it is network-reachable without credentials. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.
- No confirmed exploitation. It is not in CISA’s KEV catalog and CISA’s SSVC assessment records no known exploitation. That can change quickly after a public write-up; re-check if you are affected.
- EPSS 0.3%, percentile 20: FIRST’s model estimates a 0.3% chance of exploitation activity in the next 30 days, higher than 20% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes
snowflake-connector-python(PyPI) < 3.18.1, fixed in 3.18.1;snowflake-connector-python(PyPI) >= 4.0.0, < 4.7.1, fixed in 4.7.1. Check your lockfile, including transitive dependencies.
What it is
Improper TLS hostname verification in Snowflake Connector for Python versions prior to 4.7.1 and 3.18.1 may have allowed a network-positioned attacker to bypass certificate hostname validation on HTTPS connections made by the connector. An attacker with on-path network access could exploit this by intercepting or redirecting network traffic and presenting a certificate signed by any trusted CA for any domain, causing the connector to accept connections without validating that the certificate matched the requested hostname. Successful exploitation requires an on-path traffic interception capability (e.g. ARP/DNS poisoning, rogue access point, BGP hijacking, or malicious proxy/exit node). This vulnerability may have exposed credentials, query data, and staged file contents to interception and tampering, and may have enabled the attacker to issue arbitrary SQL within the context of the victim's connector session. Impact is limited by the privileges of the affected Snowflake role. The fix is available in Snowflake Connector for Python versions 4.7.1 and 3.18.1. Users must manually upgrade.
From the GitHub advisory
Improper TLS hostname verification in Snowflake Connector for Python versions prior to 4.7.1 and 3.18.1 may have allowed a network-positioned attacker to bypass certificate hostname validation on HTTPS connections made by the connector. An attacker with on-path network access could exploit this by intercepting or redirecting network traffic and presenting a certificate signed by any trusted CA for any domain, causing the connector to accept connections without validating that the certificate matched the requested hostname. Successful exploitation requires an on-path traffic interception capability (e.g. ARP/DNS poisoning, rogue access point, BGP hijacking, or malicious proxy/exit node). This vulnerability may have exposed credentials, query data, and staged file contents to interception and tampering, and may have enabled the attacker to issue arbitrary SQL within the context of the victim's connector session. Impact is limited by the privileges of the affected Snowflake role. The fix is available in Snowflake Connector for Python versions 4.7.1 and 3.18.1. Users must manually upgrade.
Weakness type: CWE-297.
Product: snowflake-connector-python (PyPI) · Assigned by: SNOWFLAKE · Published: 2026-07-16
Affected and fixed versions
| Ecosystem | Package | Vulnerable | First fixed |
|---|---|---|---|
| PyPI | snowflake-connector-python | < 3.18.1 | 3.18.1 |
| PyPI | snowflake-connector-python | >= 4.0.0, < 4.7.1 | 4.7.1 |
| Vendor | Product | Affected versions (per CVE record) |
|---|---|---|
| Snowflake | Snowflake Connector for Python | 3.17.4 < 3.18.1, 4.0.0 < 4.7.1 |
Severity scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| SNOWFLAKE | 4.0 | 9.2 Critical | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N |
| GitHub | 4.0 | 9.2 | CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:L/SC:N/SI:N/SA:N |
- Attack vector: network (remotely reachable)
- Attack complexity: low
- Attack requirements: present (depends on deployment conditions)
- Privileges required: none (no login)
- User interaction: none
CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.
Exploitation and urgency
- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation none, automatable yes, technical impact total.
- FIRST EPSS (model of 2026-10-21): 0.29% probability of exploitation activity in the next 30 days; percentile 20.
Timeline
- — CVE record last updated
- — CVE record published by SNOWFLAKE
- — GitHub-reviewed advisory GHSA-5cc2-282f-jjq2 published (critical)
Sources and references
Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.
Vulnerability records
- GitHub Advisory GHSA-5cc2-282f-jjq2 github.com
- CVE.org record CVE-2026-15925 cve.org
- NVD entry CVE-2026-15925 nvd.nist.gov
Other references from the CVE record and advisory
- Snowflake Connector for Python 3.18.1 Release Notes github.com
- Snowflake Connector for Python 4.7.1 Release Notes github.com
- github.com github.com