Web IsolationApplication · Symantec

CVE-2018-12246

MEDIUM · 6.1 CVSS v3.0 Published 2018-10-22
Fix available
A fix is available. Upgrade to 1.11.21 or later.
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
Symantec Web Isolation (WI) 1.11 prior to 1.11.21 is susceptible to a reflected cross-site scripting (XSS) vulnerability. A remote attacker can target end users protected by WI with social engineering attacks using crafted URLs for legitimate web sites. A successful attack allows injecting malicious JavaScript code into the website's rendered copy running inside the end user's web browser. It does not allow injecting code into the real (isolated) copy of the website running on the WI Threat Isolation Engine.

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

Symantec Web Isolation versions prior to 1.11.21 contain a reflected cross-site scripting (XSS) vulnerability in how the product processes and renders web content. Attackers can craft malicious URLs that, when clicked by end users, cause JavaScript code to execute within the browser's rendered copy of websites, but the isolation architecture prevents this from affecting the actual isolated copy on the Threat Isolation Engine.

MitigationUpgrade to Symantec Web Isolation version 1.11.21 or later to address the reflected XSS vulnerability.

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
Web IsolationApplication
Affected:>= 1.11, < 1.11.21

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. Confirm Symantec Web Isolation is deployed
    Check your inventory or network for instances of Symantec Web Isolation (formerly known as Web Security or similar threat isolation solutions). Look for the Threat Isolation Engine component.
    Affected if The product is present in your environment
  2. Locate the product version
    Access the Symantec Web Isolation admin console or CLI interface. The version is typically displayed on the dashboard, in system settings, or obtainable via command line (consult product documentation for exact CLI command).
    Affected if You cannot determine the version
  3. Compare installed version against vulnerable range
    Note the exact version number (e.g., 1.11.0, 1.11.15, 1.11.21, 1.12). Compare it to the affected range: versions 1.11 through 1.11.20.x are vulnerable.
    Affected if Installed version is 1.11.x where x is any version prior to 21, or version 1.11 with no sub-version (implying earliest 1.11 release)
  4. Assess user exposure to URL-based attacks
    Review web traffic logs and proxy logs for users accessing Symantec Web Isolation. Determine if end users interact with URLs from untrusted sources that could contain crafted malicious payloads.
    Affected if Users routinely click external URLs within the isolated browsing sessions

You are affected if Symantec Web Isolation version 1.11 through 1.11.20 (or any 1.11.x version prior to 1.11.21) is installed and users can click on maliciously crafted URLs.

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
Upgrade available Upgrade to 1.11.21 or later
Fixed in 1.11.21
Interim mitigation

Upgrade to Symantec Web Isolation version 1.11.21 or later to address the reflected XSS vulnerability.

Fix this in Web Isolation Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,560
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $4,096.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2018-12246 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

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-2018-12246 in production — separate from our analysis above.

No notes yet

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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
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data