CVE-2016-9899Firefox Use-After-Free
Use-after-free while manipulating DOM events and removing audio elements due to errors in the handling of node adoption.
Published Jun 11, 2018 · Updated Aug 4, 2026 · Also known as DEBIAN-CVE-2016-9899, UBUNTU-CVE-2016-9899
Key Facts
Patch immediately- CVE-2016-9899 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Firefox (Mozilla), Thunderbird (Mozilla), Debian Linux and 22 more products.
- It is not listed in any known-exploited vulnerabilities catalog. A public exploit is reported by tracking sources, but no code link is listed yet.
- EPSS estimates a 21% probability of exploitation in the next 30 days.
- Fixed versions are available, including Firefox 0:45.6.0-1.el5_11, Firefox 0:45.6.0-1.el6_8, Firefox 0:45.6.0-1.el7_3.
- Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
Scores
CVSS v3.1
9.8
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
21%
Higher than 97.5% of all scored CVEs
Exploit maturity
Proof of concept
ATLAS score
43/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Not listed
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Proof of concept
Public exploit code
1
Proof-of-concept links
In-the-wild evidence
1
Reports of active use
Advisories And Exploit References
- advisoryhttps://security-tracker.debian.org/tracker/CVE-2016-9899
- advisoryhttps://ubuntu.com/security/CVE-2016-9899
- advisoryhttps://www.cve.org/CVERecord?id=CVE-2016-9899
- advisoryRHSA-2016:2946
- advisoryRHSA-2016:2973
- advisoryRHSA-2016:2946
Description
Use-after-free while manipulating DOM events and removing audio elements due to errors in the handling of node adoption. This vulnerability affects Firefox < 50.1, Firefox ESR < 45.6, and Thunderbird < 45.6.
Affected Products
144 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| FirefoxMozilla | >= unspecified | 52.1.0 |
| ThunderbirdMozilla | >= unspecified | 52.1.0 |
| Debian LinuxDebian | 9.0 | n/a |
| Enterprise LinuxRedhat | 5.0, 6.0, 7.0 | n/a |
| Enterprise Linux DesktopRedhat | 5.0, 6.0, 7.0 | n/a |
Patched Releases
Firefox
0:45.6.0-1.el5_11, 0:45.6.0-1.el6_8, 0:45.6.0-1.el7_3, 45.6.0-1.0.1.el5_11, 45.6.0-1.0.1.el6_8, 45.6.0-1.0.1.el7_3, 50.1.0-1, 50.1.0+build2-0ubuntu0.14.04.1, 50.1.0+build2-0ubuntu0.16.04.1, 50.1, 52.1.0
Firefox ESR
45.6, 128.5.1-1.1, 45.6.0, 45.6.0esr-1, 45.6.0esr-1~deb7u1, 45.6.0esr-1~deb8u1
firefox-esr-branding-upstream
128.5.1-1.1
firefox-esr-translations-common
128.5.1-1.1
firefox-esr-translations-other
128.5.1-1.1
icedove
1:45.6.0-1~deb8u1, 1:45.6.0-2~deb7u1
Thunderbird
52.1.0, 0:45.6.0-1.el5_11, 0:45.6.0-1.el6_8, 0:45.6.0-1.el7_3, 1:45.7.0+build1-0ubuntu0.14.04.1, 1:45.7.0+build1-0ubuntu0.16.04.1, 45.6.0-1.0.1.el5_11, 45.6.0-1.0.1.el6_8, 45.6.0-1.0.1.el7_3, 45.6
MozillaFirefox
45.6.0esr-62.1, 45.6.0esr-66.1, 45.6.0esr-96.1, 50.1.0-1.1, 50.1.0-45.1
MozillaFirefox-branding-upstream
50.1.0-1.1, 50.1.0-45.1
MozillaFirefox-buildsymbols
50.1.0-1.1, 50.1.0-45.1
MozillaFirefox-devel
45.6.0esr-62.1, 45.6.0esr-96.1, 50.1.0-1.1, 50.1.0-45.1
MozillaFirefox-translations
45.6.0esr-62.1, 45.6.0esr-66.1, 45.6.0esr-96.1
MozillaFirefox-translations-common
50.1.0-1.1, 50.1.0-45.1
MozillaFirefox-translations-other
50.1.0-1.1, 50.1.0-45.1
MozillaThunderbird
45.6.0-20.1, 91.1.1-1.1
MozillaThunderbird-buildsymbols
45.6.0-20.1
MozillaThunderbird-devel
45.6.0-20.1
MozillaThunderbird-translations-common
45.6.0-20.1, 91.1.1-1.1
MozillaThunderbird-translations-other
45.6.0-20.1, 91.1.1-1.1
Timeline
Publicly disclosed
Jun 11, 2018
Last updated
Aug 4, 2026
Weakness Type
- CWE-416 Use After Free
References
- advisorysecurity-tracker.debian.org · CVE-2016-9899
- advisoryubuntu.com · CVE-2016-9899
- advisorycve.org · CVERecord
- advisoryRHSA-2016:2946
- advisoryRHSA-2016:2973
FAQ
Common Questions.
Use-after-free while manipulating DOM events and removing audio elements due to errors in the handling of node adoption.
Affected: Firefox (Mozilla) versions >= unspecified; Thunderbird (Mozilla) versions >= unspecified; Debian Linux versions 9.0, among others. The full list is in the CVE brief.
It is not listed in any known-exploited vulnerabilities catalog.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
A public exploit is reported by tracking sources, but no code link is listed yet.
Fixed versions are available, including Firefox 0:45.6.0-1.el5_11, Firefox 0:45.6.0-1.el6_8, Firefox 0:45.6.0-1.el7_3.
Brandefense priority: patch immediately, because public exploit code exists for a high-severity flaw.
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