firefox: Possible integer overflow to fix inside XML_Parse in Expat
Published Jun 11, 2018
9.8
CRITICALCVSS 3.1
EPSS 5.47%
Description
An integer overflow during the parsing of XML using the Expat library. This vulnerability affects Firefox < 50.
Affected products
-
- Version unspecifiedStatusaffectedConstraints<50
- Version
Configuration 2
- 8.0
- 9.0
- 10.0
No data.
Red Hat Enterprise Linux 5
expat
Will not fix
Red Hat Enterprise Linux 5
firefox
Not affected
Red Hat Enterprise Linux 5
thunderbird
Not affected
Red Hat Enterprise Linux 6
compat-expat1
Will not fix
Red Hat Enterprise Linux 6
expat
Will not fix
Red Hat Enterprise Linux 6
firefox
Not affected
Red Hat Enterprise Linux 6
thunderbird
Not affected
Red Hat Enterprise Linux 7
expat
Will not fix
Red Hat Enterprise Linux 7
firefox
Not affected
Red Hat Enterprise Linux 7
python
Not affected
Red Hat Enterprise Linux 7
thunderbird
Not affected
Red Hat Enterprise Virtualization 3
mingw-virt-viewer
Will not fix
Red Hat JBoss Enterprise Application Platform 6
httpd
Will not fix
Red Hat JBoss Enterprise Web Server 2
expat
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | expat | Will not fix | n/a |
| Red Hat Enterprise Linux 5 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 5 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 6 | compat-expat1 | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | expat | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 6 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 7 | expat | Will not fix | n/a |
| Red Hat Enterprise Linux 7 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 7 | python | Not affected | n/a |
| Red Hat Enterprise Linux 7 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Virtualization 3 | mingw-virt-viewer | Will not fix | n/a |
| Red Hat JBoss Enterprise Application Platform 6 | httpd | Will not fix | n/a |
| Red Hat JBoss Enterprise Web Server 2 | expat | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue does not affect the version of firefox and thunderbird as shipped with Red Hat Enterprise Linux 5, 6 and 7.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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 (17 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 5.47% (0.05472) | 92.51th | v5 (v2026.06.15) |
| Jun 15, 2026 | 5.54% (0.05542) | 91.80th | v5 (v2026.06.15) |
| Sep 1, 2025 | 2.11% (0.02108) | 83.49th | v4 (v2025.03.14) |
| Jul 26, 2025 | 1.07% (0.01072) | 76.80th | v4 (v2025.03.14) |
| Mar 30, 2025 | 2.31% (0.02307) | 83.30th | v4 (v2025.03.14) |
| Mar 29, 2025 | 13.50% (0.13502) | 90.34th | v4 (v2025.03.14) |
| Mar 17, 2025 | 2.83% (0.02833) | 85.26th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.95% (0.00951) | 83.86th | v3 (v2023.03.01) |
| Dec 12, 2023 | 0.95% (0.00951) | 81.38th | v3 (v2023.03.01) |
| Nov 2, 2023 | 1.45% (0.01448) | 85.22th | v3 (v2023.03.01) |
| Jul 10, 2023 | 1.40% (0.01395) | 84.55th | v3 (v2023.03.01) |
| Jun 5, 2023 | 1.38% (0.01383) | 84.39th | v3 (v2023.03.01) |
| Mar 7, 2023 | 1.07% (0.01073) | 81.97th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.11% (0.01108) | 55.18th | v2 (v2022.01.01) |
| Sep 17, 2022 | 1.11% (0.01108) | 53.57th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.11% (0.01108) | 51.54th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.11% (0.01108) | 29.61th | v2 (v2022.01.01) |
References (11)
- http://www.securityfocus.com/bid/94337 vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1037298 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- http://www.securitytracker.com/id/1039427 vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry
- https://access.redhat.com/security/cve/CVE-2016-9063 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=1274777 x_refsource_CONFIRMIssue TrackingVendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1396540 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2016-9063
- https://www.cve.org/CVERecord?id=CVE-2016-9063
- https://www.debian.org/security/2017/dsa-3898 vendor-advisoryx_refsource_DEBIANThird Party Advisory
- https://www.mozilla.org/en-US/security/advisories/mfsa2016-89/#CVE-2016-9063
- https://www.mozilla.org/security/advisories/mfsa2016-89/ x_refsource_CONFIRMVendor Advisory
| Link | Providers | Tags |
|---|---|---|
| http://www.securityfocus.com/bid/94337 | vdb-entryx_refsource_BIDThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1037298 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| http://www.securitytracker.com/id/1039427 | vdb-entryx_refsource_SECTRACKThird Party AdvisoryVDB Entry | |
| https://access.redhat.com/security/cve/CVE-2016-9063 | Vendor Advisory | |
| https://bugzilla.mozilla.org/show_bug.cgi?id=1274777 | x_refsource_CONFIRMIssue TrackingVendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1396540 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2016-9063 | ||
| https://www.cve.org/CVERecord?id=CVE-2016-9063 | ||
| https://www.debian.org/security/2017/dsa-3898 | vendor-advisoryx_refsource_DEBIANThird Party Advisory | |
| https://www.mozilla.org/en-US/security/advisories/mfsa2016-89/#CVE-2016-9063 | ||
| https://www.mozilla.org/security/advisories/mfsa2016-89/ | x_refsource_CONFIRMVendor Advisory |
Change history (0)
No recorded changes yet.