CVE-2026-18596 (CVSS 8.1)

Description

An authentication bypass using an alternate path or channel vulnerability in the OTP in Synology DiskStation Manager (DSM) before 7.3.2-86009-5 and 7.4.1-90080-1 allows remote attackers with valid user credentials to read or write arbitrary files and conduct denial-of-service attacks.

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CVSS v3.1 Score

8.1

HIGH

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

EPSS — Exploit Prediction

0.0066

Probability of exploitation

0.52%

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-288 CWE-288

References

Other References

https://www.synology.com/en-global/security/advisory/Synology_SA_26_18

Frequently Asked Questions

What is CVE-2026-18596? +

An authentication bypass using an alternate path or channel vulnerability in the OTP in Synology DiskStation Manager (DSM) before 7.3.2-86009-5 and 7.4.1-90080-1 allows remote attackers with valid user credentials to read or write arbitrary files and conduct denial-of-service attacks. It has a CVSS v3.1 base score of 8.1 (HIGH).

How severe is CVE-2026-18596? +

CVE-2026-18596 has a CVSS v3.1 score of 8.1 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0066, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-18596? +

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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