dbcve.org
Nas OsOperating system · Seagate

CVE-2018-12302

MEDIUM · 6.1 CVSS v3.0 Published 2019-05-13
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
68/100
Remediation priority · Elevated
Remotely reachable No privileges

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
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.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Session cookies in Seagate NAS OS 4.3.15.1 are not marked with the HTTPOnly flag, allowing JavaScript in XSS attacks to access and exfiltrate session tokens. Attackers can hijack user sessions by stealing the unprotected cookie values.

MitigationSet the HTTPOnly attribute on all session cookies in the web application to prevent JavaScript access via XSS. This is typically configured at the application or server level when cookies are created.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Nas OsOperating system
Affected:= 4.3.15.1

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Scope
Changed
Confidentiality
Low
Integrity
Low
Availability
None

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Verify Seagate NAS OS version
    Access the NAS admin dashboard (typically https://<nas-ip>) and navigate to System Settings or About page to confirm the installed NAS OS version number.
    Affected if Version is 4.3.15.1
  2. Identify session cookies
    Log into the NAS admin interface and use browser developer tools (F12 > Application/Storage tab > Cookies) or capture network traffic to locate session cookies used for authentication (often named 'session', 'sid', 'PHPSESSID', or similar).
    Affected if Session cookies exist after authentication
  3. Inspect HTTPOnly flag on session cookies
    In browser developer tools, examine the HttpOnly column for each session cookie, or inspect the Set-Cookie response headers in network capture. HTTPOnly should be set to prevent JavaScript access.
    Affected if Session cookies are missing the HTTPOnly attribute (column shows false or flag is absent in headers)

You are affected if running Seagate NAS OS version 4.3.15.1 and session cookies lack the HTTPOnly flag, allowing XSS to steal authentication tokens.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Set the HTTPOnly attribute on all session cookies in the web application to prevent JavaScript access via XSS. This is typically configured at the application or server level when cookies are created.

Fix this in Nas Os Scoped from the published advisory
  • Consultation3.0 h
  • Implementation6.0 h
  • Testing4.0 h
  • Review / QA2.0 h
15.0 hours of engineering $2,640
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2018-12302 in production — separate from our analysis above.

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
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  • Version or environment caveats, and links to real fixes
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