CVE-2026-3303

LOW
Published Oct 19, 2026 Modified Oct 20, 2026 CWE-942

Description

IBM Concert 1.0 through 3.0.0 uses cross-origin resource sharing (CORS) which could allow an attacker to carry out privileged actions as the domain name is not being limited to only trusted domains.

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CVSS v3.1 Score

3.7
LOW
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N

EPSS — Exploit Prediction

0.0026
Probability of exploitation
0.16%
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-942 CWE-942

References

Frequently Asked Questions

What is CVE-2026-3303? +
IBM Concert 1.0 through 3.0.0 uses cross-origin resource sharing (CORS) which could allow an attacker to carry out privileged actions as the domain name is not being limited to only trusted domains. It has a CVSS v3.1 base score of 3.7 (LOW).
How severe is CVE-2026-3303? +
CVE-2026-3303 has a CVSS v3.1 score of 3.7 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0026, placing it in the 0th percentile for exploitation probability.
How do I check if I'm vulnerable to CVE-2026-3303? +
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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