CVE-2026-15541: Auth Bypass (CVSS 7.3)

Description

A flaw has been found in will-moss Isaiah up to 1.36.9. The impacted element is the function Server.Handle of the file app/server/server/server.go of the component Master Websocket Handler. Executing a manipulation of the argument Agent can lead to missing authorization. It is possible to launch the attack remotely. The pull request to fix this issue awaits acceptance.

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CVSS v3.1 Score

7.3

HIGH

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

EPSS — Exploit Prediction

0.0032

Probability of exploitation

0.24%

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-862 Missing Authorization

CWE-863 Incorrect Authorization

References

Other References

https://github.com/will-moss/isaiah/ https://github.com/will-moss/isaiah/issues/34 https://github.com/will-moss/isaiah/pull/35 https://vuldb.com/cve/CVE-2026-15541 https://vuldb.com/submit/855074 https://vuldb.com/vuln/377891 https://vuldb.com/vuln/377891/cti

Frequently Asked Questions

What is CVE-2026-15541? +

A flaw has been found in will-moss Isaiah up to 1.36.9. The impacted element is the function Server.Handle of the file app/server/server/server.go of the component Master Websocket Handler. Executing a manipulation of the argument Agent can lead to missing authorization. It is possible to launch the attack remotely. The pull request to fix this issue awaits acceptance. It has a CVSS v3.1 base score of 7.3 (HIGH).

How severe is CVE-2026-15541? +

CVE-2026-15541 has a CVSS v3.1 score of 7.3 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0032, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-15541? +

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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