Mozilla: CORS preflight is bypassed when non-standard Content-Type headers are received (MFSA 2015-127)
Published Nov 5, 2015
7.5
HIGHCVSS 2.0
EPSS 2.84%
Description
Mozilla Firefox before 42.0 and Firefox ESR 38.x before 38.4 improperly follow the CORS cross-origin request algorithm for the POST method in situations involving an unspecified Content-Type header manipulation, which allows remote attackers to bypass the Same Origin Policy by leveraging the lack of a preflight-request step.
Affected products
No data.
Configuration 1
No data.
Red Hat Enterprise Linux 5
firefox-0:38.4.0-1.el5_11
Fixed · RHSA-2015:1982
Red Hat Enterprise Linux 5
thunderbird-0:38.4.0-1.el5_11
Fixed · RHSA-2015:2519
Red Hat Enterprise Linux 6
firefox-0:38.4.0-1.el6_7
Fixed · RHSA-2015:1982
Red Hat Enterprise Linux 6
thunderbird-0:38.4.0-1.el6_7
Fixed · RHSA-2015:2519
Red Hat Enterprise Linux 7
firefox-0:38.4.0-1.ael7b_1
Fixed · RHSA-2015:1982
Red Hat Enterprise Linux 7
thunderbird-0:38.4.0-1.el7_2
Fixed · RHSA-2015:2519
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | firefox-0:38.4.0-1.el5_11 | Fixed | RHSA-2015:1982 |
| Red Hat Enterprise Linux 5 | thunderbird-0:38.4.0-1.el5_11 | Fixed | RHSA-2015:2519 |
| Red Hat Enterprise Linux 6 | firefox-0:38.4.0-1.el6_7 | Fixed | RHSA-2015:1982 |
| Red Hat Enterprise Linux 6 | thunderbird-0:38.4.0-1.el6_7 | Fixed | RHSA-2015:2519 |
| Red Hat Enterprise Linux 7 | firefox-0:38.4.0-1.ael7b_1 | Fixed | RHSA-2015:1982 |
| Red Hat Enterprise Linux 7 | thunderbird-0:38.4.0-1.el7_2 | Fixed | RHSA-2015:2519 |
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.
No CVSS v3.0 score for this CVE.
AV:N/AC:L/Au:N/C:P/I:P/A:P
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 (10 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.84% (0.02841) | 86.18th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.84% (0.02841) | 84.78th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.58% (0.00581) | 66.35th | v4 (v2025.03.14) |
| Mar 29, 2025 | 1.66% (0.01656) | 70.57th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.58% (0.00581) | 67.01th | v4 (v2025.03.14) |
| Dec 12, 2024 | 2.69% (0.02692) | 90.83th | v3 (v2023.03.01) |
| Mar 7, 2023 | 2.69% (0.02692) | 88.80th | v3 (v2023.03.01) |
| Mar 6, 2023 | 4.36% (0.04358) | 88.02th | v2 (v2022.01.01) |
| Apr 1, 2022 | 4.36% (0.04358) | 86.83th | v2 (v2022.01.01) |
| Feb 4, 2022 | 4.36% (0.04358) | 70.59th | v2 (v2022.01.01) |
References (25)
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00013.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00015.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00020.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00021.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-security-announce/2015-11/msg00025.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-updates/2015-12/msg00037.html vendor-advisoryx_refsource_SUSE
- http://lists.opensuse.org/opensuse-updates/2015-12/msg00049.html vendor-advisoryx_refsource_SUSE
- http://rhn.redhat.com/errata/RHSA-2015-1982.html vendor-advisoryx_refsource_REDHAT
- http://rhn.redhat.com/errata/RHSA-2015-2519.html vendor-advisoryx_refsource_REDHAT
- http://www.debian.org/security/2015/dsa-3393 vendor-advisoryx_refsource_DEBIAN
- http://www.debian.org/security/2015/dsa-3410 vendor-advisoryx_refsource_DEBIAN
- http://www.mozilla.org/security/announce/2015/mfsa2015-127.html x_refsource_CONFIRMVendor Advisory
- http://www.oracle.com/technetwork/topics/security/bulletinapr2016-2952098.html x_refsource_CONFIRM
- http://www.oracle.com/technetwork/topics/security/linuxbulletinoct2015-2719645.html x_refsource_CONFIRM
- http://www.securityfocus.com/bid/77411 vdb-entryx_refsource_BID
- http://www.securitytracker.com/id/1034069 vdb-entryx_refsource_SECTRACK
- http://www.ubuntu.com/usn/USN-2785-1 vendor-advisoryx_refsource_UBUNTU
- http://www.ubuntu.com/usn/USN-2819-1 vendor-advisoryx_refsource_UBUNTU
- https://access.redhat.com/security/cve/CVE-2015-7193 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1210302 x_refsource_CONFIRM
- https://bugzilla.redhat.com/show_bug.cgi?id=1277346 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2015-7193
- https://security.gentoo.org/glsa/201512-10 vendor-advisoryx_refsource_GENTOO
- https://www.cve.org/CVERecord?id=CVE-2015-7193
- https://www.mozilla.org/security/announce/2015/mfsa2015-127.html
Change history (0)
No recorded changes yet.