CVEvulnerability
CVE-2026-48818
7.5 HIGH
Official page ↗
- Status
- Modified
- Published
- 2026-06-17
- Last modified
- 2026-10-26
- Assigner
- [email protected]
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- CVSS 3.1 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c)
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- Weaknesses
- CWE-918
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.
Affected configurations
• encode starlette (< 1.1.0)
Related
Weakness · CWE (1)
- CWE-918 Server-Side Request Forgery weakness
References
- https://github.com/Kludex/starlette/commit/fd53168a7767b6b55ba5af787fd88f49e33cabc5 Patch
- https://github.com/Kludex/starlette/pull/3287 Patch
- https://github.com/Kludex/starlette/releases/tag/1.1.0 Release Notes
- https://github.com/Kludex/starlette/security/advisories/GHSA-wqp7-x3pw-xc5r Mitigation, Vendor Advisory
- https://github.com/pypa/advisory-database/tree/main/vulns/starlette/PYSEC-2026-2281.yaml github.com
- https://access.redhat.com/errata/RHSA-2026:30087 access.redhat.com
- https://access.redhat.com/errata/RHSA-2026:30088 access.redhat.com
- https://access.redhat.com/errata/RHSA-2026:30089 access.redhat.com
- https://access.redhat.com/security/cve/CVE-2026-48818 access.redhat.com
- https://bugzilla.redhat.com/show_bug.cgi?id=2490020 bugzilla.redhat.com
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48818.json security.access.redhat.com