---
id: "CVE-2026-17337"
page: "https://infrastack.ai/live/CVE-2026-17337"
kind: "vulnerability"
aliases: ["CVE-2026-17337"]
title: "IBM API Connect: improper certificate check lets authenticated attacker bypass authentication"
severity: "high"
cvss: 7.4
epss: null
exploited: false
status: "open"
category: "runtime"
products: [{"name": "IBM API Connect V12 OnPrem", "fixed": ["12.1.1.3"], "affected": ">= 12.1.0.0, <= 12.1.1.2", "ecosystem": "vendor"}]
ecosystems: []
tags: ["api-gateway", "ibm-api-connect", "runtime", "self-hosted"]
not_affected_if: ["versions-outside-12.1.0.0-to-12.1.1.2"]
published_at: "2026-11-07T05:18:44+00:00"
first_seen_at: "2026-11-07T05:46:04+00:00"
updated_at: "2026-11-07T06:15:26+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-17337", "first_seen_at": "2026-11-07T05:46:04+00:00"}, {"source": "analyst", "url": "https://www.ibm.com/support/pages/node/7295635", "first_seen_at": "2026-11-07T06:15:26+00:00", "cites": ["https://www.ibm.com/support/pages/node/7295635"]}]
exploit_sources: []
---

# IBM API Connect: improper certificate check lets authenticated attacker bypass authentication

Link for people: https://infrastack.ai/live/CVE-2026-17337 (this .md is for agents)

IBM API Connect V12 OnPrem v12.1.0.0 through v12.1.1.2 does not perform a certificate check reliably in all cases, so a connection may be accepted without proper authentication. IBM fixed it in v12.1.1.3 and lists no workarounds.

_Summary, check and fix written by a model from the sources; labelled as such._

## Affected

- vendor:IBM API Connect V12 OnPrem affected >= 12.1.0.0, <= 12.1.1.2 fixed 12.1.1.3

## How to check

Check your API Connect V12 on-prem version. Exposed if it is between v12.1.0.0 and v12.1.1.2 inclusive; v12.1.1.3 or later is fixed. IBM's bulletin does not name a specific certificate configuration.

## Fix

Upgrade IBM API Connect to v12.1.1.3 (Fix Central: https://www.ibm.com/support/pages/node/7290205)

## Timeline

- 2026-11-07T05:46:04+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-17337
- 2026-11-07T06:15:26+00:00 analyst https://www.ibm.com/support/pages/node/7295635 — Read IBM bulletin node/7295635 (fixed v12.1.1.3, affected V12 OnPrem 12.1.0.0-12.1.1.2, workarounds: None). Bulletin CWE-362 mismatches the description (certificate validation); CVSS vector says PR:N while text says authenticated. No exploitation or PoC found; did not search social posts. Part of a multi-CVE bulletin.

## Documents

- [advisory] IBM Security Bulletin: Multiple Vulnerabilities in IBM API Connect (v12.1.1.3) https://www.ibm.com/support/pages/node/7295635

## From the sources

IBM API Connect 12.1.0.0 through 12.1.1.2 could allow a remote authenticated attacker to bypass authentication due to improper certificate validation. A certificate check is not performed reliably in all cases, which could allow a connection to be accepted without proper authentication.

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