CVE-2026-13666 (CVSS 3.5)

Description

An improper neutralization of CRLF sequences ('CRLF Injection') vulnerability in Sharing API in Synology DiskStation Manager (DSM) before 7.2.1-69057-12, 7.2.2-72806-9, 7.3.2-86009-4 and 7.4-90075 allows remote authenticated users to write limited files when a victim clicks a sharing URL.

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CVSS v3.1 Score

3.5

LOW

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

EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.15%

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-93 CWE-93

References

Other References

https://www.synology.com/en-global/security/advisory/Synology_SA_26_13

Frequently Asked Questions

What is CVE-2026-13666? +

An improper neutralization of CRLF sequences ('CRLF Injection') vulnerability in Sharing API in Synology DiskStation Manager (DSM) before 7.2.1-69057-12, 7.2.2-72806-9, 7.3.2-86009-4 and 7.4-90075 allows remote authenticated users to write limited files when a victim clicks a sharing URL. It has a CVSS v3.1 base score of 3.5 (LOW).

How severe is CVE-2026-13666? +

CVE-2026-13666 has a CVSS v3.1 score of 3.5 out of 10, rated LOW. This is a low-severity vulnerability with limited impact. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-13666? +

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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