CVE-2026-18633

HIGH

Published Nov 12, 2026 Modified Nov 12, 2026 CWE-824

Description

An access of uninitialized pointer vulnerability in the nfsd in Synology DiskStation Manager (DSM) before 7.3.2-86009-5 and 7.4.1-90080-1 allows remote attackers to conduct denial-of-service attacks.

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CVSS v3.1 Score

7.5

HIGH

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

EPSS — Exploit Prediction

0.0076

Probability of exploitation

0.56%

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-824 CWE-824

References

Other References

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

Frequently Asked Questions

What is CVE-2026-18633? +

An access of uninitialized pointer vulnerability in the nfsd in Synology DiskStation Manager (DSM) before 7.3.2-86009-5 and 7.4.1-90080-1 allows remote attackers to conduct denial-of-service attacks. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-18633? +

CVE-2026-18633 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0076, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-18633? +

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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