VULNERABILITY INTELLIGENCE

CVE-2026-48818

CVSS score7.5 HIGH
EPSS probability0.37%
CISA KEVNot currently listed
Published2026-06-17
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Description

Starlette is a lightweight ASGI framework/toolkit. In versions 1.0.1 and earlier, StaticFiles on Windows is vulnerable to SSRF. An UNC path such as \\attacker.com\share can cause os.path.realpath to initiate an outbound SMB connection before the path is rejected, exposing the service account’s NTLMv2 credentials for offline cracking or relay even though the HTTP response is only a 404. The issue affects default follow_symlink=False deployments, including frameworks built on Starlette such as FastAPI; POSIX systems and follow_symlink=True are unaffected. The issue is fixed in 1.1.0.

Weakness classification

  • security-advisories@github.com: CWE-918
  • 0b0ca135-0b70-47e7-9f44-1890c2a1c46c: CWE-918

Primary references