What is CVE-2018-12302?

CVE-2018-12302 is a medium-severity vulnerability in Seagate Nas OS, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2019-05-13.

How severe is CVE-2018-12302?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Seagate Nas OS

CVE-2018-12302

Missing HTTPOnly flag on session cookies in the Seagate NAS OS version 4.3.15.1 web application allows attackers to steal session tokens via cross-site scripting.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2019-05-13 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.008 (54.9th percentile), scored 2026-09-29.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 55th percentile — 54.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.008 · newest: 0.008 · change: 0.000

Affected products

Seagate Nas OS — versions 4.3.15.1

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

blog.securityevaluators.com/invading-your-personal-cloud-ise-labs-exploits-the-… (Third Party Advisory)

Frequently asked questions

What is CVE-2018-12302?: CVE-2018-12302 is a medium-severity vulnerability in Seagate Nas OS, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2019-05-13.
How severe is CVE-2018-12302?: Medium severity. CVSS v3 base score is 6.1 out of 10.