CVE-2016-9904
An attacker could use a JavaScript Map/Set timing attack to determine whether an atom is used by another compartment/zone in specific contexts.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (2.66%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.0
- 7.5 HIGHCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
- EPSS
- 2.66% probability · 86th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-200
- Affected
- redhat/enterprise linux desktop · redhat/enterprise linux server · redhat/enterprise linux workstation · debian/debian linux · mozilla/firefox · mozilla/thunderbird
- Source
- security@mozilla.org
EPSS 2.7% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- http://rhn.redhat.com/errata/RHSA-2016-2946.htmlThird Party Advisory
- http://www.securityfocus.com/bid/94885Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1037461Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1317936Issue Tracking, Patch
- https://security.gentoo.org/glsa/201701-15Third Party Advisory
- https://www.debian.org/security/2017/dsa-3757Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2016-94/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2016-95/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2016-96/Vendor Advisory
- http://rhn.redhat.com/errata/RHSA-2016-2946.htmlThird Party Advisory
- http://www.securityfocus.com/bid/94885Third Party Advisory, VDB Entry
- http://www.securitytracker.com/id/1037461Third Party Advisory, VDB Entry
- https://bugzilla.mozilla.org/show_bug.cgi?id=1317936Issue Tracking, Patch
- https://security.gentoo.org/glsa/201701-15Third Party Advisory
- https://www.debian.org/security/2017/dsa-3757Third Party Advisory
- https://www.mozilla.org/security/advisories/mfsa2016-94/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2016-95/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2016-96/Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.