Mozilla: Add-on update site certificate pin expiration (MFSA 2016-85, MFSA 2016-86)
Published Sep 22, 2016
7.4
HIGHCVSS 3.0
EPSS 2.37%
Description
Mozilla Firefox before 49.0, Firefox ESR 45.x before 45.4, and Thunderbird < 45.4 rely on unintended expiration dates for Preloaded Public Key Pinning, which allows man-in-the-middle attackers to spoof add-on updates by leveraging possession of an X.509 server certificate for addons.mozilla.org signed by an arbitrary built-in Certification Authority.
Affected products
No data.
No data.
Red Hat Enterprise Linux 5
firefox-0:45.4.0-1.el5_11
Fixed · RHSA-2016:1912
Red Hat Enterprise Linux 6
firefox-0:45.4.0-1.el6_8
Fixed · RHSA-2016:1912
Red Hat Enterprise Linux 7
firefox-0:45.4.0-1.el7_2
Fixed · RHSA-2016:1912
Red Hat Enterprise Linux 5
thunderbird
Not affected
Red Hat Enterprise Linux 6
thunderbird
Not affected
Red Hat Enterprise Linux 7
thunderbird
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | firefox-0:45.4.0-1.el5_11 | Fixed | RHSA-2016:1912 |
| Red Hat Enterprise Linux 6 | firefox-0:45.4.0-1.el6_8 | Fixed | RHSA-2016:1912 |
| Red Hat Enterprise Linux 7 | firefox-0:45.4.0-1.el7_2 | Fixed | RHSA-2016:1912 |
| Red Hat Enterprise Linux 5 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 6 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 7 | 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:C/C:H/I:N/A:N
AV:N/AC:M/Au:N/C:P/I:N/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
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (9 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.37% (0.02373) | 83.23th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.38% (0.02382) | 81.66th | v5 (v2026.06.15) |
| Mar 17, 2025 | 0.46% (0.00462) | 62.14th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.24% (0.00240) | 62.92th | v3 (v2023.03.01) |
| Jun 20, 2024 | 0.24% (0.00240) | 62.22th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.24% (0.00240) | 60.20th | v3 (v2023.03.01) |
| Mar 6, 2023 | 2.69% (0.02686) | 82.85th | v2 (v2022.01.01) |
| Apr 1, 2022 | 2.69% (0.02686) | 81.17th | v2 (v2022.01.01) |
| Feb 4, 2022 | 2.69% (0.02686) | 62.66th | v2 (v2022.01.01) |
References (18)
- http://rhn.redhat.com/errata/RHSA-2016-1912.html vendor-advisoryx_refsource_REDHAT
- http://seclists.org/dailydave/2016/q3/51 mailing-listx_refsource_MLISTThird Party Advisory
- http://www.debian.org/security/2016/dsa-3674 vendor-advisoryx_refsource_DEBIAN
- http://www.mozilla.org/security/announce/2016/mfsa2016-85.html x_refsource_CONFIRMRelease Notes
- http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2016-3090545.html x_refsource_CONFIRM
- http://www.securityfocus.com/bid/93049 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1036852 vdb-entryx_refsource_SECTRACK
- https://access.redhat.com/security/cve/CVE-2016-5284 Vendor Advisory
- https://blog.mozilla.org/security/2016/09/16/update-on-add-on-pinning-vulnerability/ x_refsource_CONFIRMThird Party AdvisoryVDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1303127 x_refsource_CONFIRMIssue TrackingThird Party AdvisoryVDB Entry
- https://bugzilla.redhat.com/show_bug.cgi?id=1377565 Issue Tracking
- https://hackernoon.com/tor-browser-exposed-anti-privacy-implantation-at-mass-scale-bd68e9eb1e95 x_refsource_MISCTechnical Description
- https://nvd.nist.gov/vuln/detail/CVE-2016-5284
- https://security.gentoo.org/glsa/201701-15 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2016-5284
- https://www.mozilla.org/security/advisories/mfsa2016-85/
- https://www.mozilla.org/security/advisories/mfsa2016-86/ x_refsource_CONFIRM
- https://www.mozilla.org/security/advisories/mfsa2016-88/ x_refsource_CONFIRM
Change history (0)
No recorded changes yet.