CVE-2016-1950

Heap-based buffer overflow in Mozilla Network Security Services (NSS) before 3.19.2.3 and 3.20.x and 3.21.x before 3.21.1, as used in Mozilla Firefox before 45.0 and Firefox ESR 38.x before 38.7, allows remote attackers to execute arbitrary code via crafted ASN.1 data in an X.509 certificate.

Published: 2016-03-13 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-1950 is rated Moderate Risk (62.7/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.87%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2016-1950

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-01-19 3.33% 1.87% -1.46%
2 2025-12-28 1.94% 3.33% +1.39%
3 2025-12-27 — 1.94% —

Full EPSS history (22 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-1950

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2016-1950

OS Trackers for CVE-2016-1950

vendor priority summary link
debian not yet assigned CVE-2016-1950 not yet assigned priority: Debian including 3 source packages (firefox, firefox-esr, nss), 11 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 11. https://security-tracker.debian.org/tracker/CVE-2016-1950
gentoo normal CVE-2016-1950: 1 GLSA(s) (201605-06), 6 atom(s) (dev-libs/nspr, dev-libs/nss, mail-client/thunderbird, mail-client/thunderbird-bin, www-client/firefox, www-client/firefox-bin); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2016-1950
redhat critical — https://access.redhat.com/security/cve/CVE-2016-1950
suse high CVE-2016-1950 severity important: SUSE including 646 source package names (MozillaFirefox, MozillaFirefox-102.11.0-150200.152.87.1, …), 1102 product×package rows across 106 product lines (Image SLES12-SP5-Azure-BYOS, Image SLES12-SP5-Azure-Basic-On-Demand, … (106 product lines)): Fixed 896, Known Affected 157, Known Not Affected 49. https://www.suse.com/security/cve/CVE-2016-1950/
ubuntu medium CVE-2016-1950 medium priority: Ubuntu including 3 source packages (firefox, nss, thunderbird), 21 status rows across 7 suites (precise, trusty, upstream, wily, xenial, yakkety, zesty): released 18, not-affected 3. https://ubuntu.com/security/CVE-2016-1950

Affected software / configurations for CVE-2016-1950

Vendor Product Version Raw CPE
mozilla network_security_services 3.19.2 cpe:2.3:a:mozilla:network_security_services:3.19.2:*:*:*:*:*:*:*
mozilla network_security_services 3.20 cpe:2.3:a:mozilla:network_security_services:3.20:*:*:*:*:*:*:*
mozilla network_security_services 3.20.1 cpe:2.3:a:mozilla:network_security_services:3.20.1:*:*:*:*:*:*:*
mozilla network_security_services 3.21 cpe:2.3:a:mozilla:network_security_services:3.21:*:*:*:*:*:*:*
mozilla firefox <= 44.0.2 cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
mozilla firefox 38.0 cpe:2.3:a:mozilla:firefox:38.0:*:*:*:*:*:*:*
mozilla firefox 38.0.1 cpe:2.3:a:mozilla:firefox:38.0.1:*:*:*:*:*:*:*
mozilla firefox 38.0.5 cpe:2.3:a:mozilla:firefox:38.0.5:*:*:*:*:*:*:*
mozilla firefox 38.1.0 cpe:2.3:a:mozilla:firefox:38.1.0:*:*:*:*:*:*:*
mozilla firefox 38.1.1 cpe:2.3:a:mozilla:firefox:38.1.1:*:*:*:*:*:*:*
mozilla firefox 38.2.0 cpe:2.3:a:mozilla:firefox:38.2.0:*:*:*:*:*:*:*
mozilla firefox 38.2.1 cpe:2.3:a:mozilla:firefox:38.2.1:*:*:*:*:*:*:*
mozilla firefox 38.3.0 cpe:2.3:a:mozilla:firefox:38.3.0:*:*:*:*:*:*:*
mozilla firefox 38.4.0 cpe:2.3:a:mozilla:firefox:38.4.0:*:*:*:*:*:*:*
mozilla firefox 38.5.0 cpe:2.3:a:mozilla:firefox:38.5.0:*:*:*:*:*:*:*
mozilla firefox 38.5.1 cpe:2.3:a:mozilla:firefox:38.5.1:*:*:*:*:*:*:*
mozilla firefox 38.6.0 cpe:2.3:a:mozilla:firefox:38.6.0:*:*:*:*:*:*:*
mozilla firefox 38.6.1 cpe:2.3:a:mozilla:firefox:38.6.1:*:*:*:*:*:*:*
oracle linux 5.0 cpe:2.3:o:oracle:linux:5.0:*:*:*:*:*:*:*
oracle linux 6 cpe:2.3:o:oracle:linux:6:*:*:*:*:*:*:*
oracle linux 7 cpe:2.3:o:oracle:linux:7:*:*:*:*:*:*:*
oracle vm_server 3.2 cpe:2.3:o:oracle:vm_server:3.2:*:*:*:*:*:*:*
apple iphone_os <= 9.2.1 cpe:2.3:o:apple:iphone_os:*:*:*:*:*:*:*:*
apple mac_os_x <= 10.11.3 cpe:2.3:o:apple:mac_os_x:*:*:*:*:*:*:*:*
apple tvos <= 9.1 cpe:2.3:o:apple:tvos:*:*:*:*:*:*:*:*
apple watchos <= 2.1 cpe:2.3:o:apple:watchos:*:*:*:*:*:*:*:*
oracle glassfish_server 2.1.1 cpe:2.3:a:oracle:glassfish_server:2.1.1:*:*:*:*:*:*:*
oracle iplanet_web_proxy_server 4.0 cpe:2.3:a:oracle:iplanet_web_proxy_server:4.0:*:*:*:*:*:*:*
oracle iplanet_web_server 7.0 cpe:2.3:a:oracle:iplanet_web_server:7.0:*:*:*:*:*:*:*
opensuse opensuse 13.1 cpe:2.3:o:opensuse:opensuse:13.1:*:*:*:*:*:*:*

References for CVE-2016-1950

URL Tags
http://lists.apple.com/archives/security-announce/2016/Mar/msg00000.html Mailing List
http://lists.apple.com/archives/security-announce/2016/Mar/msg00001.html Mailing List
http://lists.apple.com/archives/security-announce/2016/Mar/msg00002.html Mailing List
http://lists.apple.com/archives/security-announce/2016/Mar/msg00004.html Mailing List
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00027.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00029.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00031.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00050.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00068.html
http://lists.opensuse.org/opensuse-security-announce/2016-03/msg00093.html
http://lists.opensuse.org/opensuse-security-announce/2016-06/msg00016.html Third Party Advisory
http://rhn.redhat.com/errata/RHSA-2016-0495.html
http://www.debian.org/security/2016/dsa-3510
http://www.debian.org/security/2016/dsa-3520
http://www.debian.org/security/2016/dsa-3688
http://www.mozilla.org/security/announce/2016/mfsa2016-35.html Vendor Advisory
http://www.oracle.com/technetwork/security-advisory/cpujul2017-3236622.html
http://www.oracle.com/technetwork/security-advisory/cpuoct2016-2881722.html Third Party Advisory
http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
http://www.oracle.com/technetwork/topics/security/linuxbulletinjan2016-2867209.html Third Party Advisory
http://www.oracle.com/technetwork/topics/security/ovmbulletinjul2016-3090546.html Third Party Advisory
http://www.securityfocus.com/bid/84223
http://www.securitytracker.com/id/1035215
http://www.ubuntu.com/usn/USN-2917-1
http://www.ubuntu.com/usn/USN-2917-2
http://www.ubuntu.com/usn/USN-2917-3
http://www.ubuntu.com/usn/USN-2924-1
http://www.ubuntu.com/usn/USN-2934-1
https://bto.bluecoat.com/security-advisory/sa119
https://bugzilla.mozilla.org/show_bug.cgi?id=1245528 Issue Tracking
https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.19.2.3_release_notes Release Notes
https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.21.1_release_notes Release Notes
https://security.gentoo.org/glsa/201605-06
https://support.apple.com/HT206166 Third Party Advisory
https://support.apple.com/HT206167 Third Party Advisory
https://support.apple.com/HT206168 Third Party Advisory
https://support.apple.com/HT206169 Third Party Advisory
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