CVE-2026-105459: api connect Signature Bypass — Fix

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 an attacker to gain unauthorized access to an organization due to improper verification of a cryptographic signature. A token is accepted without its signature being fully verified, which could allow an attacker to join an organization without a valid invitation.

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CVSS v3.1 Score

6.8

MEDIUM

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:N/I:H/A:N

EPSS — Exploit Prediction

0.0021

Probability of exploitation

0.11%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-347 CWE-347

Affected Products

Vendor	Product	Versions
ibm	api_connect	10.0.8.0 — 10.0.8.13
ibm	api_connect	12.1.0.0 — 12.1.1.3

References

Advisories & Patches

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

Frequently Asked Questions

What is CVE-2026-105459? +

IBM API Connect 10.0.8.0 through 10.0.8.12 and 12.1.0.0 through 12.1.1.2 could allow an attacker to gain unauthorized access to an organization due to improper verification of a cryptographic signature. A token is accepted without its signature being fully verified, which could allow an attacker to join an organization without a valid invitation. It has a CVSS v3.1 base score of 6.8 (MEDIUM).

How severe is CVE-2026-105459? +

CVE-2026-105459 has a CVSS v3.1 score of 6.8 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0021, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-105459? +

CVE-2026-105459 affects products from ibm, specifically: api_connect. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-105459? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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