`CVE-2016-9843` zlib

Affected software	zlib
Severity	9.8 Critical CVSS 3.1 2 scores
Published	23 May 2017
Updated	17 Jun 2026

Description

The crc32_big function in crc32.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact via vectors involving big-endian CRC calculation.

Exploitation status

No public exploit

No exploit has been reported in the sources we check. Published 9 years ago.

CISA KEV not listed
VulnCheck KEV not listed
CISA Vulnrichment no assessment published
Indexed PoC none indexed
EPSS 5.8% chance in 30 days

Waratek protection

Outside Waratek scope

A Java vulnerability, but not one Waratek protects. It affects only Java on a user's desktop (applets, Web Start, JavaFX, the installer), sits in a product the Waratek agent can't be installed into, or is in a package we don't expect in business applications. The decision below says which.

Protection none
Action not pursued none
Review human Researcher
Record active

Decided by	Manual classification of this CVE in the legacy dataset
Finding	A manual classification set this CVE's status to Outside Waratek scope, but the CVE names a tracked product.

Decided by

Manual classification of this CVE in the legacy dataset

Finding

A manual classification set this CVE's status to Outside Waratek scope, but the CVE names a tracked product.

CVSS

9.8 CRITICAL v3.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H 2 metrics

We show the highest score from the newest CVSS version. Scores from different versions can't be compared, and the first score listed is sometimes a 0.0 placeholder.

Version Score Band Vector Assigner Type

CVSS 3.1 9.8 CRITICAL CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H NVD Primary published

CVSS 2.0 7.5 none AV:N/AC:L/Au:N/C:P/I:P/A:P NVD Primary

Version	Score	Band	Vector	Assigner	Type
CVSS 3.1	9.8	CRITICAL	`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H`	NVD	Primary	published
CVSS 2.0	7.5	none	`AV:N/AC:L/Au:N/C:P/I:P/A:P`	NVD	Primary

Affected software and releases

Oracle advisories

Advisory	Type	Quarter	Products Oracle names in its risk matrix
Oracle Critical Patch Update July 2020 ↗	CPU	2020-Q3	Oracle Database Server / Core RDBMS (zlib) (18c)
Oracle Critical Patch Update October 2018 ↗	CPU	2018-Q4	Oracle MySQL / InnoDB (zlib) (5.5.61 and prior, 5.6.41 and prior, 5.7.23 and prior, 8.0.12 and prior)
Oracle Critical Patch Update July 2018 ↗	CPU	2018-Q3	Oracle Fusion Middleware / Outside In Search Export SDK (zlib) (8.5.3) Oracle's note: Outside In Technology is a suite of software development kits (SDKs). The protocol and CVSS score depend on the software that uses the Outside In Technology code. The CVSS score assumes that the software passes data received over a network directly to Outside In Technology code, but if data is not received over a network the CVSS score may be lower.

Advisory

Type

Quarter

Products Oracle names in its risk matrix

Oracle Critical Patch Update July 2020 ↗

CPU

2020-Q3

Oracle Database Server / Core RDBMS (zlib) (18c)

Oracle Critical Patch Update October 2018 ↗

CPU

2018-Q4

Oracle MySQL / InnoDB (zlib) (5.5.61 and prior, 5.6.41 and prior, 5.7.23 and prior, 8.0.12 and prior)

Oracle Critical Patch Update July 2018 ↗

CPU

2018-Q3

Oracle Fusion Middleware / Outside In Search Export SDK (zlib) (8.5.3)
Oracle's note: Outside In Technology is a suite of software development kits (SDKs). The protocol and CVSS score depend on the software that uses the Outside In Technology code. The CVSS score assumes that the software passes data received over a network directly to Outside In Technology code, but if data is not received over a network the CVSS score may be lower.

Oracle components and versions

Family	Component	Versions, as Oracle lists them	Read as
Oracle Database Server	Core RDBMS (zlib)	18c	18
Oracle Fusion Middleware	Outside In Search Export SDK (zlib)	8.5.3	8.5.3
Oracle MySQL	InnoDB (zlib)	5.5.61 and prior, 5.6.41 and prior, 5.7.23 and prior, 8.0.12 and prior

Family

Component

Versions, as Oracle lists them

Read as

Oracle Database Server

Core RDBMS (zlib)

18c

Oracle Fusion Middleware

Outside In Search Export SDK (zlib)

8.5.3

Oracle MySQL

InnoDB (zlib)

5.5.61 and prior, 5.6.41 and prior, 5.7.23 and prior, 8.0.12 and prior

Products and versions

24 products, 46 version entries

Source	Vendor	Product	Scheme	Affected versions
nvd	apple	iphone os	generic	＜ 11
nvd	apple	mac os x	generic	≥ 10.0.0 and ＜ 10.13.0
nvd	apple	tvos	generic	＜ 11.0
nvd	apple	watchos	generic	＜ 4
nvd	canonical	ubuntu linux	generic	16.04 · 18.04
nvd	debian	debian linux	generic	8.0
nvd	mariadb	mariadb	generic	≥ 5.5.0 and ＜ 5.5.62 · ≥ 10.0.0 and ＜ 10.0.37 · ≥ 10.1.0 and ＜ 10.1.37 · ≥ 10.2.0 and ＜ 10.2.19 · ≥ 10.3.0 and ＜ 10.3.11
nvd	netapp	active iq unified manager	generic	≥ 7.3 · ≥ 9.5
nvd	netapp	oncommand insight	generic	any version
nvd	netapp	oncommand workflow automation	generic	any version
nvd	netapp	snapcenter	generic	any version
nvd	nodejs	node.js	generic	≥ 4.0.0 and ≤ 4.1.2 · ≥ 4.2.0 and ＜ 4.8.2 · ≥ 6.0.0 and ≤ 6.8.1 · ≥ 6.9.0 and ＜ 6.10.2 · ≥ 7.0.0 and ＜ 7.6.0
nvd	opensuse	leap	generic	42.1 · 42.2
nvd	opensuse	opensuse	generic	13.2
nvd	oracle	database server	generic	18c
nvd	oracle	jdk	javase	1.6.0:update161 · 1.7.0:update151 · 1.8.0:update144
nvd	oracle	jre	javase	1.6.0:update161 · 1.7.0:update151 · 1.8.0:update144
nvd	oracle	mysql	generic	≥ 5.5.0 and ≤ 5.5.61 · ≥ 5.6.0 and ≤ 5.6.41 · ≥ 5.7.0 and ≤ 5.7.23 · ≥ 8.0.0 and ≤ 8.0.12
nvd	redhat	enterprise linux desktop	generic	6.0 · 7.0
nvd	redhat	enterprise linux eus	generic	7.4 · 7.5
nvd	redhat	enterprise linux server	generic	6.0 · 7.0
nvd	redhat	enterprise linux workstation	generic	6.0 · 7.0
nvd	redhat	satellite	generic	5.8
nvd	zlib	zlib	generic	≥ 1.2.0 and ＜ 1.2.9

Source

Vendor

Product

Scheme

Affected versions

nvd

apple

iphone os

generic

＜ 11

nvd

apple

mac os x

generic

≥ 10.0.0 and ＜ 10.13.0

nvd

apple

tvos

generic

＜ 11.0

nvd

apple

watchos

generic

＜ 4

nvd

canonical

ubuntu linux

generic

16.04 · 18.04

nvd

debian

debian linux

generic

8.0

nvd

mariadb

generic

≥ 5.5.0 and ＜ 5.5.62 · ≥ 10.0.0 and ＜ 10.0.37 · ≥ 10.1.0 and ＜ 10.1.37 · ≥ 10.2.0 and ＜ 10.2.19 · ≥ 10.3.0 and ＜ 10.3.11

nvd

netapp

active iq unified manager

generic

≥ 7.3 · ≥ 9.5

nvd

netapp

oncommand insight

generic

any version

nvd

netapp

oncommand workflow automation

generic

any version

nvd

netapp

snapcenter

generic

any version

nvd

nodejs

node.js

generic

≥ 4.0.0 and ≤ 4.1.2 · ≥ 4.2.0 and ＜ 4.8.2 · ≥ 6.0.0 and ≤ 6.8.1 · ≥ 6.9.0 and ＜ 6.10.2 · ≥ 7.0.0 and ＜ 7.6.0

nvd

opensuse

leap

generic

42.1 · 42.2

nvd

opensuse

generic

13.2

nvd

oracle

database server

generic

18c

nvd

oracle

jdk

javase

1.6.0:update161 · 1.7.0:update151 · 1.8.0:update144

nvd

oracle

jre

javase

1.6.0:update161 · 1.7.0:update151 · 1.8.0:update144

nvd

oracle

mysql

generic

≥ 5.5.0 and ≤ 5.5.61 · ≥ 5.6.0 and ≤ 5.6.41 · ≥ 5.7.0 and ≤ 5.7.23 · ≥ 8.0.0 and ≤ 8.0.12

nvd

redhat

enterprise linux desktop

generic

6.0 · 7.0

nvd

redhat

enterprise linux eus

generic

7.4 · 7.5

nvd

redhat

enterprise linux server

generic

6.0 · 7.0

nvd

redhat

enterprise linux workstation

generic

6.0 · 7.0

nvd

redhat

satellite

generic

5.8

nvd

zlib

generic

≥ 1.2.0 and ＜ 1.2.9

Earlier manual review

A reviewer classified this CVE in an older dataset. We kept the labels and products below, but not the reviewer's reasoning.

## Manual Classification Context **Labels:** HTTP, MYSQL PROTOCOL, CREATE SESSION, INNODB (ZLIB), SEE NOTE 1, OUTSIDE IN SEARCH EXPORT SDK (ZLIB), NO AUTH REMOTE EXPLOIT, ORACLE NET **Products:** CORE RDBMS (ZLIB), ORACLE DATABASE SERVER, ZLIB, ORACLE OUTSIDE IN TECHNOLOGY, MYSQL SERVER, ORACLE FUSION MIDDLEWARE, ORACLE MYSQL

References

URL	Tags
https://access.redhat.com/errata/RHSA-2017:1220	ADVISORY, RHSA-2017:1220
https://access.redhat.com/security/cve/CVE-2016-9843	REPORT, RHSA-2017:1220
https://access.redhat.com/errata/RHSA-2017:2999	ADVISORY, RHSA-2017:2999
https://access.redhat.com/errata/RHSA-2017:3453	ADVISORY, RHSA-2017:3453
http://lists.opensuse.org/opensuse-updates/2016-12/msg00127.html
http://lists.opensuse.org/opensuse-updates/2017-01/msg00050.html
http://lists.opensuse.org/opensuse-updates/2017-01/msg00053.html
http://www.openwall.com/lists/oss-security/2016/12/05/21
http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html
http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html

URL

Timeline

Published	2017-05-23	By the CVE Program.
NVD record modified	2026-06-17	NVD's own last-modified date for this record.

Published

2017-05-23

By the CVE Program.

NVD record modified

2026-06-17

NVD's own last-modified date for this record.

How VRT decided (5 of 24 rules ran)

5 of 24 rules ran. The rest didn't run because an earlier rule had already settled the CVE.

# Rule Outcome Status Detail

identity: Does this identifier describe a vulnerability at all? the first rule that matches decides

1 rejected no match CVE Program withdrawal of this identifier

scope: Is it a vulnerability Waratek protects? the first rule that matches decides

2 armr-patch-file no match An ARMR patch file on disk for this CVE

3 armr-secure-rule-file no match An ARMR security-rule template on disk for this CVE

4 manual-classification no match A researcher's recorded decision for this specific CVE

5 manual classification decided it matched Outside Waratek scope Found in legacy manual classifications

6 non-java-upstream not reached A root cause in non-Java code: an OS kernel, a C library, or a bundled runtime

7 oracle-component not reached The defect being in a component of a tracked product the agent does not reach: JavaFX, the Java SE installer, the JInitiator browser plug-in, the native WebLogic proxy plug-in, or a native part of Oracle Application Server or Collaboration Suite (HTTP Server, Web Cache, Internet Directory, mail and calendar servers). Oracle gives these no CPE of their own and names them only in the description.

8 java-client-side not reached Oracle's own risk-matrix note saying the CVE is reached only through untrusted code in the Java sandbox (applets, Web Start) or only through a client installation of Java, so a server running its own trusted code is not exposed

9 osv-maven not reached An OSV.dev record of this CVE affecting a package published to Maven Central. When every such package is one business applications do not use (Minecraft mods and launchers, Fastjson) and no tracked product is named by CPE, it settles the CVE as Outside Waratek scope instead

10 cna-maven-package not reached An affected Maven artifact named by the CNA itself

11 known-cpe-product not reached An NVD CPE naming a product ARMR tracks

12 cna-cpe-product not reached A CPE the CNA published naming a tracked product. Oracle publishes these on advisory day, months before NVD.

13 oracle-advisory-family not reached A tracked product family named in Oracle's own risk matrix. CPE cannot carry a suite name, only a module.

14 cna-named-product not reached A tracked product named in words by the CVE's own CNA, on a record with no CPE yet. Apache and Eclipse publish these on advisory day, before NVD adds CPE data.

15 non-deployable-product not reached The only affected product being a sealed appliance image, where Java runs but no -javaagent can be attached

16 unmatched-product not reached No tracked product matched above, and none present at all

disposition: What do we do about one that is? every rule runs

17 patch-hint not reached A reference pointing at the upstream fix: a commit, a PR, a Red Hat bug

18 open-source-maven not reached The affected package being open source on Maven, so the fix can be read

19 poc-derivable not reached An indexed exploit clearing the evidence bar to reverse-engineer, where there is no source to read

20 no-exploit not reached Nothing to build a rule from yet: no published exploit, no CISA record of exploitation and no source-level change to read

21 secure-rule-match not reached A vulnerability class already blocked by an ARMR security rule

22 exploited-no-fix-or-poc not reached Somebody exploiting this CVE (a CISA or VulnCheck KEV listing, or a CISA verdict of active exploitation), with no fix, source code or PoC to build a rule from

23 below-action-threshold not reached Medium or Low severity, no CISA or VulnCheck KEV listing, no PoC clearing the evidence bar, no CISA verdict, no Oracle advisory

24 no-exploit-published not reached Exploit code for this candidate, published in a reviewed catalogue or a GitHub repository with 5 or more stars, or in use per CISA or VulnCheck; not only a CISA verdict, a forecast, or nothing at all

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