Mozilla: WebExtension content scripts can execute in disallowed contexts
Published Feb 28, 2019
6.5
MEDIUMCVSS 3.0
EPSS 2.27%
Description
A vulnerability where a WebExtension can run content scripts in disallowed contexts following navigation or other events. This allows for potential privilege escalation by the WebExtension on sites where content scripts should not be run. This vulnerability affects Firefox ESR < 60.3 and Firefox < 63.
Affected products
-
- Version unspecifiedStatusaffectedConstraints<63
- Version
-
- Version unspecifiedStatusaffectedConstraints<60.3
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Mozilla | Firefox | n/a |
| ||||||
| Mozilla | Firefox ESR | n/a |
|
Configuration 1
- < 63.0
- < 60.3
Configuration 2
- 8.0
- 9.0
Configuration 3
- 14.04
- 16.04
- 18.04
- 18.10
Configuration 4
- 6.0
- 7.0
- 6.0
- 7.0
- 7.6
- 7.6
- 7.6
- 6.0
- 7.0
No data.
Red Hat Enterprise Linux 6
firefox-0:60.3.0-1.el6
Fixed · RHSA-2018:3006
Red Hat Enterprise Linux 7
firefox-0:60.3.0-1.el7_5
Fixed · RHSA-2018:3005
Red Hat Enterprise Linux 6
thunderbird
Not affected
Red Hat Enterprise Linux 7
thunderbird
Not affected
Red Hat Enterprise Linux 8
firefox
Not affected
Red Hat Enterprise Linux 8
thunderbird
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 6 | firefox-0:60.3.0-1.el6 | Fixed | RHSA-2018:3006 |
| Red Hat Enterprise Linux 7 | firefox-0:60.3.0-1.el7_5 | Fixed | RHSA-2018:3005 |
| Red Hat Enterprise Linux 6 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 7 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 8 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 8 | thunderbird | Not affected | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:N
1 other source (Red Hat) ▾
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
AV:N/AC:M/Au:N/C:N/I:P/A:N
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.27% (0.02273) | 82.45th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.27% (0.02273) | 80.73th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.73% (0.00730) | 70.99th | v4 (v2025.03.14) |
| Dec 17, 2024 | 0.23% (0.00234) | 61.03th | v3 (v2023.03.01) |
| Dec 13, 2024 | 1.60% (0.01598) | 87.89th | v3 (v2023.03.01) |
| Feb 22, 2024 | 3.18% (0.03181) | 90.85th | v3 (v2023.03.01) |
| Sep 3, 2023 | 2.60% (0.02600) | 88.95th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.99% (0.01994) | 87.00th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
| Feb 3, 2022 | 2.63% (0.02627) | 55.32th | v5 (v2026.06.15) |
| Apr 14, 2021 | 2.63% (0.02627) | 0.00th | v1 |
References (16)
- http://www.securityfocus.com/bid/105718 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1041944 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://access.redhat.com/errata/RHSA-2018:3005 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/errata/RHSA-2018:3006 vendor-advisoryx_refsource_REDHATThird Party Advisory
- https://access.redhat.com/security/cve/CVE-2018-12396 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1483602 x_refsource_CONFIRMBroken LinkIssue TrackingVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1642186 Issue Tracking
- https://lists.debian.org/debian-lts-announce/2018/11/msg00008.html mailing-listx_refsource_MLISTThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2018-12396
- https://security.gentoo.org/glsa/201811-04 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://usn.ubuntu.com/3801-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2018-12396
- https://www.debian.org/security/2018/dsa-4324 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- https://www.mozilla.org/en-US/security/advisories/mfsa2018-27/#CVE-2018-12396
- https://www.mozilla.org/security/advisories/mfsa2018-26/ x_refsource_CONFIRMVendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2018-27/ x_refsource_CONFIRMVendor Advisory
Change history (0)
No recorded changes yet.