An existing mitigation of timing side-channel attacks is insufficient in some circumstances.

published 2018-06-11 8 y ago modified 2026-06-17 4 mo ago also EUVD-2016-9895

cvss: 5.9; version 3.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 2.4%; EPSS 2.4% chance of exploitation in 30 days, percentile 83%
public exploits: 0; none known

An existing mitigation of timing side-channel attacks is insufficient in some circumstances. This issue is addressed in Network Security Services (NSS) 3.26.1. This vulnerability affects Thunderbird < 45.5, Firefox ESR < 45.5, and Firefox < 50.

Patch / fix

fixed in 3 distros 4

Mozilla Thunderbird 45.5
Mozilla Firefox ESR 45.5
Mozilla Firefox 50

debian ubuntu suse opensuse

nss Debian 14, Debian 13, Debian 12 2:3.26.2-1
firefox-esr Debian 14, Debian 13, Debian 12 45.5.0esr-1

debian advisories DEBIAN-CVE-2016-9074

nss Ubuntu 14.04 LTS 2:3.26.2-0ubuntu0.14.04.3
nss Ubuntu 16.04 LTS 2:3.26.2-0ubuntu0.16.04.2

ubuntu advisories UBUNTU-CVE-2016-9074

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

mozilla-nss SLES for SAP 11 SP4, SLES 11 SP4, SLES 11 SP3-TERADATA +6 more 3.21.3-39.1
MozillaFirefox SLES for SAP 11 SP4, SLES 11 SP4, SLES 11 SP3-TERADATA +6 more 45.5.1esr-59.1
mozilla-nss SLES for SAP 12 SP2, SLES for SAP 12 SP1, SLES for SAP 12 +8 more 3.21.3-50.1
MozillaFirefox SLES for SAP 12 SP2, SLES for SAP 12 SP1, SLES for SAP 12 +8 more 45.5.0esr-88.1
mozilla-nss SLES 11 SP2-LTSS 3.21.3-30.1
MozillaFirefox SLES 11 SP2-LTSS 45.5.1esr-63.1

suse advisories SUSE-SU-2016:3105-1 SUSE-SU-2016:3080-1 SUSE-SU-2016:3014-1

firefox-esr openSUSE Tumbleweed 128.5.1-1.1
MozillaFirefox openSUSE Tumbleweed 50.1.0-1.1

opensuse advisories openSUSE-SU-2024:14572-1 openSUSE-SU-2024:10071-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2016-9074 updated 2026-11-05 cvss 3.7

nss: Insufficient timing side-channel resistance in divSpoiler

Red Hat Enterprise Linux 5 nss Red Hat Enterprise Linux 6 nss, nss-tools, nss-sysinit Red Hat Enterprise Linux 7 nss, nss-tools, nss-sysinit
affected: no fix planned “Will not fix”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

2.36% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
NVD	3.0	5.9	CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	4.3	AV:N/AC:M/Au:N/C:P/I:N/A:N

Affected products

Mozilla Thunderbird
Mozilla Firefox ESR
Mozilla Firefox

Classification

Weakness

CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

debian.org /security/2016/dsa-3730
vendor-advisory, third-party-advisory
security.gentoo.org /glsa/201701-46
vendor-advisory, third-party-advisory
security.gentoo.org /glsa/201701-15
vendor-advisory, third-party-advisory
bugzilla.mozilla.org /show_bug.cgi?id=1293334
issue-tracking, vendor-advisory
mozilla.org /security/advisories/mfsa2016-93/
vendor-advisory
mozilla.org /security/advisories/mfsa2016-89/
vendor-advisory
mozilla.org /security/advisories/mfsa2016-90/
vendor-advisory
securityfocus.com /bid/94341
vdb-entry, third-party-advisory
securitytracker.com /id/1037298
vdb-entry, third-party-advisory

Sources

CVE List CVE-2016-9074
NVD CVE-2016-9074

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary