CVE-2016-5423

PostgreSQL before 9.1.23, 9.2.x before 9.2.18, 9.3.x before 9.3.14, 9.4.x before 9.4.9, and 9.5.x before 9.5.4 allow remote authenticated users to cause a denial of service (NULL pointer dereference and server crash), obtain sensitive memory information, or possibly execute arbitrary code via (1) a CASE expression within the test value subexpression of another CASE or (2) inlining of an SQL function that implements the equality operator used for a CASE expression involving values of different types.

Published: 2016-12-09 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-5423 is rated High Risk (68.1/100): CVSS High severity, with high exploitation likelihood (EPSS 6.01%, 92th percentile). EPSS ranks this CVE among the most likely to be exploited in the near term. EPSS rose +2.61% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize 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-2016-5423

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 2026-06-15 3.40% 6.01% +2.61%
2 2026-03-11 2.71% 3.40% +0.69%
3 2026-02-19 — 2.71% —

Full EPSS history (18 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-5423

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.3 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/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:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
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 5.5 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.0 6.4 [email protected]

Weakness enumeration for CVE-2016-5423

OS Trackers for CVE-2016-5423

vendor priority summary link
gentoo normal CVE-2016-5423: 1 GLSA(s) (201701-33), 1 atom(s) (dev-db/postgresql); latest impact normal. https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2016-5423
redhat medium — https://access.redhat.com/security/cve/CVE-2016-5423
suse medium CVE-2016-5423 severity moderate: SUSE including 64 source package names (libecpg6-32bit-9.5.4-1.2, libecpg6-9.4.9-0.19.1, …), 118 product×package rows across 19 product lines (SUSE Liberty Linux 7, SUSE Linux Enterprise Desktop 12 SP1, … (19 product lines)): Fixed 117, Known Not Affected 1. https://www.suse.com/security/cve/CVE-2016-5423/
ubuntu medium CVE-2016-5423 medium priority: Ubuntu including 4 source packages (postgresql-8.4, postgresql-9.1, postgresql-9.3, postgresql-9.5), 24 status rows across 6 suites (precise, trusty, upstream, xenial, yakkety, zesty): DNE 14, released 7, ignored 1, needs-triage 1, not-affected 1. https://ubuntu.com/security/CVE-2016-5423

Affected software / configurations for CVE-2016-5423

Vendor Product Version Raw CPE
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
postgresql postgresql <= 9.1.22 cpe:2.3:a:postgresql:postgresql:*:*:*:*:*:*:*:*
postgresql postgresql 9.2 cpe:2.3:a:postgresql:postgresql:9.2:*:*:*:*:*:*:*
postgresql postgresql 9.2.1 cpe:2.3:a:postgresql:postgresql:9.2.1:*:*:*:*:*:*:*
postgresql postgresql 9.2.2 cpe:2.3:a:postgresql:postgresql:9.2.2:*:*:*:*:*:*:*
postgresql postgresql 9.2.3 cpe:2.3:a:postgresql:postgresql:9.2.3:*:*:*:*:*:*:*
postgresql postgresql 9.2.4 cpe:2.3:a:postgresql:postgresql:9.2.4:*:*:*:*:*:*:*
postgresql postgresql 9.2.5 cpe:2.3:a:postgresql:postgresql:9.2.5:*:*:*:*:*:*:*
postgresql postgresql 9.2.6 cpe:2.3:a:postgresql:postgresql:9.2.6:*:*:*:*:*:*:*
postgresql postgresql 9.2.7 cpe:2.3:a:postgresql:postgresql:9.2.7:*:*:*:*:*:*:*
postgresql postgresql 9.2.8 cpe:2.3:a:postgresql:postgresql:9.2.8:*:*:*:*:*:*:*
postgresql postgresql 9.2.9 cpe:2.3:a:postgresql:postgresql:9.2.9:*:*:*:*:*:*:*
postgresql postgresql 9.2.10 cpe:2.3:a:postgresql:postgresql:9.2.10:*:*:*:*:*:*:*
postgresql postgresql 9.2.11 cpe:2.3:a:postgresql:postgresql:9.2.11:*:*:*:*:*:*:*
postgresql postgresql 9.2.12 cpe:2.3:a:postgresql:postgresql:9.2.12:*:*:*:*:*:*:*
postgresql postgresql 9.2.13 cpe:2.3:a:postgresql:postgresql:9.2.13:*:*:*:*:*:*:*
postgresql postgresql 9.2.14 cpe:2.3:a:postgresql:postgresql:9.2.14:*:*:*:*:*:*:*
postgresql postgresql 9.2.15 cpe:2.3:a:postgresql:postgresql:9.2.15:*:*:*:*:*:*:*
postgresql postgresql 9.2.16 cpe:2.3:a:postgresql:postgresql:9.2.16:*:*:*:*:*:*:*
postgresql postgresql 9.2.17 cpe:2.3:a:postgresql:postgresql:9.2.17:*:*:*:*:*:*:*
postgresql postgresql 9.3 cpe:2.3:a:postgresql:postgresql:9.3:*:*:*:*:*:*:*
postgresql postgresql 9.3.1 cpe:2.3:a:postgresql:postgresql:9.3.1:*:*:*:*:*:*:*
postgresql postgresql 9.3.2 cpe:2.3:a:postgresql:postgresql:9.3.2:*:*:*:*:*:*:*
postgresql postgresql 9.3.3 cpe:2.3:a:postgresql:postgresql:9.3.3:*:*:*:*:*:*:*
postgresql postgresql 9.3.4 cpe:2.3:a:postgresql:postgresql:9.3.4:*:*:*:*:*:*:*
postgresql postgresql 9.3.5 cpe:2.3:a:postgresql:postgresql:9.3.5:*:*:*:*:*:*:*
postgresql postgresql 9.3.6 cpe:2.3:a:postgresql:postgresql:9.3.6:*:*:*:*:*:*:*
postgresql postgresql 9.3.7 cpe:2.3:a:postgresql:postgresql:9.3.7:*:*:*:*:*:*:*
postgresql postgresql 9.3.8 cpe:2.3:a:postgresql:postgresql:9.3.8:*:*:*:*:*:*:*
postgresql postgresql 9.3.9 cpe:2.3:a:postgresql:postgresql:9.3.9:*:*:*:*:*:*:*
postgresql postgresql 9.3.10 cpe:2.3:a:postgresql:postgresql:9.3.10:*:*:*:*:*:*:*
postgresql postgresql 9.3.11 cpe:2.3:a:postgresql:postgresql:9.3.11:*:*:*:*:*:*:*
postgresql postgresql 9.3.12 cpe:2.3:a:postgresql:postgresql:9.3.12:*:*:*:*:*:*:*
postgresql postgresql 9.3.13 cpe:2.3:a:postgresql:postgresql:9.3.13:*:*:*:*:*:*:*
postgresql postgresql 9.4 cpe:2.3:a:postgresql:postgresql:9.4:*:*:*:*:*:*:*
postgresql postgresql 9.4.1 cpe:2.3:a:postgresql:postgresql:9.4.1:*:*:*:*:*:*:*
postgresql postgresql 9.4.2 cpe:2.3:a:postgresql:postgresql:9.4.2:*:*:*:*:*:*:*
postgresql postgresql 9.4.3 cpe:2.3:a:postgresql:postgresql:9.4.3:*:*:*:*:*:*:*
postgresql postgresql 9.4.4 cpe:2.3:a:postgresql:postgresql:9.4.4:*:*:*:*:*:*:*
postgresql postgresql 9.4.5 cpe:2.3:a:postgresql:postgresql:9.4.5:*:*:*:*:*:*:*
postgresql postgresql 9.4.6 cpe:2.3:a:postgresql:postgresql:9.4.6:*:*:*:*:*:*:*
postgresql postgresql 9.4.7 cpe:2.3:a:postgresql:postgresql:9.4.7:*:*:*:*:*:*:*
postgresql postgresql 9.4.8 cpe:2.3:a:postgresql:postgresql:9.4.8:*:*:*:*:*:*:*
postgresql postgresql 9.5 cpe:2.3:a:postgresql:postgresql:9.5:*:*:*:*:*:*:*
postgresql postgresql 9.5.1 cpe:2.3:a:postgresql:postgresql:9.5.1:*:*:*:*:*:*:*
postgresql postgresql 9.5.2 cpe:2.3:a:postgresql:postgresql:9.5.2:*:*:*:*:*:*:*
postgresql postgresql 9.5.3 cpe:2.3:a:postgresql:postgresql:9.5.3:*:*:*:*:*:*:*

References for CVE-2016-5423

URL Tags
http://rhn.redhat.com/errata/RHSA-2016-1781.html
http://rhn.redhat.com/errata/RHSA-2016-1820.html
http://rhn.redhat.com/errata/RHSA-2016-1821.html
http://rhn.redhat.com/errata/RHSA-2016-2606.html
http://www.debian.org/security/2016/dsa-3646 Third Party Advisory
http://www.securityfocus.com/bid/92433 Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1036617 Third Party Advisory VDB Entry
https://access.redhat.com/errata/RHSA-2017:2425
https://bugzilla.redhat.com/show_bug.cgi?id=1364001 Issue Tracking Third Party Advisory VDB Entry
https://security.gentoo.org/glsa/201701-33
https://www.postgresql.org/about/news/1688/ Patch Vendor Advisory
https://www.postgresql.org/docs/current/static/release-9-1-23.html Release Notes Vendor Advisory
https://www.postgresql.org/docs/current/static/release-9-2-18.html Release Notes Vendor Advisory
https://www.postgresql.org/docs/current/static/release-9-3-14.html Release Notes Vendor Advisory
https://www.postgresql.org/docs/current/static/release-9-4-9.html Release Notes Vendor Advisory
https://www.postgresql.org/docs/current/static/release-9-5-4.html Release Notes Vendor Advisory
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