Symantec Web Isolation (WI) 1.11 prior to 1.11.21 is susceptible to a reflected cross-site scripting (XSS) vulnerability.

published 2018-10-22 8y ago modified 2026-06-17 4mo ago also EUVD-2018-4224

cvss: 6.1; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.0%; EPSS 1.0% chance of exploitation in 30 days, percentile 63%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

symantec web_isolation 1.11.21

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Exploit prediction

1.00% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.0	6.1	CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:N/I:P/A:N

Affected products

Symantec Corporation Symantec Web Isolation

Classification

Weakness

CWE-79 Improper Neutralization of Input During Web Page Generation

References

support.symantec.com /content/unifiedweb/en_US/article.SYMSA1464.html
vendor-advisory
securityfocus.com /bid/105581
vdb-entry, third-party-advisory

Sources

CVE List CVE-2018-12246
NVD CVE-2018-12246

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