CVE-2026-9186CWE-284broken-access-control

CVE-2026-9186

Medium · published September 4, 2026

CVSS v3.1
6.5
EPSS
0%
Percentile
31.0
In the wild
Unconfirmed
What it is

IBM Langflow OSS 1.0.0 through 1.11.2 allows remote authenticated attackers to bypass localhost-only MCP configuration installation by spoofing X-Forwarded-For: 127.0.0.1 header, enabling arbitrary writes to IDE config files (~/.cursor/mcp.json, etc.).

The record
Technical detail
CVSS v3.1
6.5 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
CVSS v4.0
Not supplied
EPSS
0.00382 · 31.0th percentile
Weakness
CWE-284 · Improper Access Control
Published
2026-09-04T19:17Z
Affected products (1)
ProductVersionsFixed in
langflow/langflow≥ 1.0.0, < 1.11.31.11.3
References (1)
https://www.ibm.com/support/pages/node/7285646 · [email protected]
EPSS history
Timeline
  • 06 SEP 03:34Z
    EPSS moved — → 0%
    epss
  • 04 SEP 14:23Z
    Langflow is vulnerable to stored cross-site scripting and IP spoofing due to unsanitized Markdown rendering and untrusted proxy header trust
    cvelistv5