Predictive Vulnerability Intelligence.

Product

  • Product
  • Pricing
  • Documentation

Company

  • About
  • Partnerships
  • Blog
  • Support

Legal

  • Terms
  • Privacy
  • Data Licensing

© 2026 FAUCET Technologies LLC. All rights reserved.

CVE-2018-12396

22
FAUCET Score

CVE-2018-12396 describes a medium-severity vulnerability in Firefox ESR and Firefox versions prior to 60.3 and 63, respectively, where a WebExtension could execute content scripts in unauthorized contexts. This flaw could lead to privilege escalation, allowing an attacker to run scripts on websites where they should be restricted. The vulnerability has a CVSS score of 6.5, indicating a network-based attack requiring user interaction, with a high impact on integrity. There is no evidence of active exploitation, public exploit code, or significant community discussion surrounding this CVE.

Impacted Technologies

VendorProductVersion(s)CPE
< 63.0CPE matchmatch criteria
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
< 60.3CPE matchmatch criteria
cpe:2.3:a:mozilla:firefox_esr:*:*:*:*:*:*:*:*
8.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
9.0CPE matchmatch criteria
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
14.04CPE matchmatch criteria
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*

CVSS Data

CVSS version used by this source: 3.0

6.5MEDIUM

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality Impact
NONE
Integrity Impact
HIGH
Availability Impact
NONE
Exploitability Score
2.8
Impact Score
3.6
CvssVersion
3.0

Exploit Intelligence

EPSS Score
2.27%
Probability of exploitation in next 30 days
EPSS Percentile
81.2%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0227 is in the 91st percentile among its peer group of 26,234 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.0 Mastodon, and 0.1 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (3)

redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 6Fixed in: firefox-0:60.3.0-1.el6
View patch
redhatpatch availablevia redhat_api
Product: Red Hat Enterprise Linux 7Fixed in: firefox-0:60.3.0-1.el7_5
View patch
mozillavendor investigatingvia nvd_reference
View patch

Vendor Advisories (1)

redhatCVE-2018-12396Moderate

Mozilla: WebExtension content scripts can execute in disallowed contexts

Oct 23, 2018

References

access.redhat.com / errata/RHSA-2018:3005
Third Party Advisory
access.redhat.com / errata/RHSA-2018:3006
Third Party Advisory
bugzilla.mozilla.org / show_bug.cgi
Broken LinkIssue TrackingVendor Advisory
lists.debian.org / debian-lts-announce/2018/11/msg00008.html
Third Party Advisory
security.gentoo.org / glsa/201811-04
Third Party Advisory
usn.ubuntu.com / 3801-1
Third Party Advisory
debian.org / security/2018/dsa-4324
Third Party Advisory
mozilla.org / security/advisories/mfsa2018-26
Vendor Advisory
mozilla.org / security/advisories/mfsa2018-27
Vendor Advisory
securityfocus.com / bid/105718
Third Party AdvisoryVDB Entry
securitytracker.com / id/1041944
Third Party AdvisoryVDB Entry