CVERadar
CRITICAL · CVSS 3.1 9.9EPSS 0.53% (p45)Threat level 50

CVE-2026-16920: CVE-2026-16920: IBM API Connect 12.1.0.0 through 12.1.1.2 could allow a remote authenticated attacker to b…

Unknown · IBM API Connect · NVD published 2026-11-07 · posted 2026-11-07 · last modified 2026-11-07

CVE-2026-16920 at a glance

CVE-2026-16920 is a critical-severity vulnerability in IBM API Connect, with a CVSS 3.1 base score of 9.9. NVD published it on 2026-11-07 and classifies the weakness as CWE-441. FIRST EPSS puts the probability of exploitation activity in the next 30 days at 0.53% (percentile 44.9, scored 2026-11-09). NVD does not list a fixed version, so the vendor advisory is the reference for the fix. Its CVERadar threat level is 50/100.

What it is

IBM API Connect 12.1.0.0 through 12.1.1.2 could allow a remote authenticated attacker to bypass security restrictions due to a confused deputy vulnerability.

WeaknessCWE-441 definition
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H (source: CNA (us.ibm.com))
ATT&CK tacticsn/a

No ATT&CK techniques could be mapped or inferred for this CVE yet.

Patches, mitigations and detection

Fixed versions

NVD does not list a fixed version for this CVE. Use the vendor advisory below.

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

No vendor-tagged reference yet; see the full reference list.

Detection Generic guidance

    Response checklist Generic guidance

    1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
    2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
    3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
    4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.

    Sources