Description
An attacker could use a JavaScript Map/Set timing attack to determine whether an atom is used by another compartment/zone in specific contexts. This could be used to leak information, such as usernames embedded in JavaScript code, across websites. This vulnerability affects Firefox < 50.1, Firefox ESR < 45.6, and Thunderbird < 45.6.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| Mozilla | Firefox | unspecified – < 50.1 | 50.1 |
| Mozilla | Firefox ESR | unspecified – < 45.6 | 45.6 |
| Mozilla | Thunderbird | unspecified – < 45.6 | 45.6 |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | firefox-esr | 45.6.0esr-1 | — |
| Debian 13 | firefox-esr | 45.6.0esr-1 | — |
| Debian 12 | firefox-esr | 45.6.0esr-1 | — |
| Debian 8 | firefox-esr | 45.6.0esr-1~deb8u1 | DSA-3734-1 |
| Debian 8 | icedove | 1:45.6.0-1~deb8u1 | DSA-3757-1 |
| Debian 7 | firefox-esr | 45.6.0esr-1~deb7u1 | DLA-743-1 |
| Debian 7 | icedove | 1:45.6.0-2~deb7u1 | DLA-782-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | firefox | 50.1.0+build2-0ubuntu0.16.04.1 | USN-3155-1 |
| Ubuntu 16.04 LTS | thunderbird | 1:45.7.0+build1-0ubuntu0.16.04.1 | USN-3165-1 |
| Ubuntu 14.04 LTS | firefox | 50.1.0+build2-0ubuntu0.14.04.1 | USN-3155-1 |
| Ubuntu 14.04 LTS | thunderbird | 1:45.7.0+build1-0ubuntu0.14.04.1 | USN-3165-1 |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 7 | firefox | 45.6.0-1.el7_3 | RHSA-2016:2946 |
| RHEL 6 | firefox | 45.6.0-1.el6_8 | RHSA-2016:2946 |
| RHEL 5 | firefox | 45.6.0-1.el5_11 | RHSA-2016:2946 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP2 | MozillaFirefox | 45.6.0esr-96.1 | SUSE-SU-2016:3222-1 |
| SLES 12 SP1 | MozillaFirefox | 45.6.0esr-96.1 | SUSE-SU-2016:3222-1 |
| SLES 12 | MozillaFirefox | 45.6.0esr-96.1 | SUSE-SU-2016:3222-1 |
| SLES 11 SP4 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
| SLES 11 SP3 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
Show 10 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 11 SP2 | MozillaFirefox | 45.6.0esr-66.1 | SUSE-SU-2016:3223-1 |
| SLES for SAP 12 SP2 | MozillaFirefox | 45.6.0esr-96.1 | SUSE-SU-2016:3222-1 |
| SLES for SAP 12 SP1 | MozillaFirefox | 45.6.0esr-96.1 | SUSE-SU-2016:3222-1 |
| SLES for SAP 12 | MozillaFirefox | 45.6.0esr-96.1 | SUSE-SU-2016:3222-1 |
| SLES for SAP 11 SP4 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
| SUSE Package Hub 12 | MozillaThunderbird | 45.6.0-20.1 | openSUSE-SU-2016:3308-1, openSUSE-SU-2016:3307-1 |
| SUSE OpenStack Cloud 5 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
| SUSE Manager Proxy 2.1 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
| SUSE Manager 2.1 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
| SUSE Linux Enterprise Point of Sale 11 SP3 | MozillaFirefox | 45.6.0esr-62.1 | SUSE-SU-2016:3210-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | MozillaFirefox | 50.1.0-1.1 | openSUSE-SU-2024:10071-1 |
| openSUSE Tumbleweed | MozillaThunderbird | 91.1.1-1.1 | openSUSE-SU-2024:10601-1 |
| openSUSE Tumbleweed | firefox-esr | 128.5.1-1.1 | openSUSE-SU-2024:14572-1 |
Alpine
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Alpine v3.4 | firefox-esr | 45.6.0 | — |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 7 | firefox | 45.6.0-1.0.1.el7_3 | ELSA-2016-2946 |
Advisories 16
- RHSA-2016:2946 Red Hat Security Advisory: firefox security update Red Hat Security Advisories (RHSA) · Jun 26, 2026
- USN-3165-1 thunderbird vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- USN-3155-1 firefox vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- DLA-782-1 icedove - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3734-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DSA-3757-1 icedove - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-743-1 firefox-esr - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2016:3210-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2016:3222-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2016:3308-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2016:3307-1 Security update for MozillaThunderbird SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:14572-1 firefox-esr-128.5.1-1.1 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:10071-1 MozillaFirefox-50.1.0-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- openSUSE-SU-2024:10601-1 MozillaThunderbird-91.1.1-1.1 on GA media SUSE / openSUSE Security Updates · May 7, 2025
- SUSE-SU-2016:3223-1 Security update for MozillaFirefox SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2016-2946 Critical: firefox security update (Oracle Linux 7) Oracle Linux Security Advisories (ELSA) · Dec 14, 2016
References
- https://www.mozilla.org/security/advisories/mfsa2016-94/
- https://bugzilla.mozilla.org/show_bug.cgi?id=1317936
- https://www.mozilla.org/security/advisories/mfsa2016-95/
- 94885 vdb-entry
- 1037461 vdb-entry
- GLSA-201701-15 vendor-advisory
- DSA-3757 vendor-advisory
- https://www.mozilla.org/security/advisories/mfsa2016-96/
- RHSA-2016:2946 vendor-advisory