CVE-2016-9840

Exploitation

Assessed, none found. CISA's assessment recorded neither public exploit code nor evidence of exploitation when it was made.

SSVC decision

• ExploitationnoneCISA recorded no public exploit code and no evidence of exploitation.
• AutomatablenoAt least one step from reconnaissance to exploitation cannot be reliably automated.
• Technical ImpacttotalSuccessful exploitation gives total control of the vulnerable component.

CISA publishes the decision points, not a final SSVC decision. The decision also depends on mission and well-being impact, which is a property of your deployment rather than of the vulnerability.

EPSS probability

4.87% probability of exploitation activity in the next 30 days.

EPSS percentile

Equal to or higher than the score of 91.8% of scored records. A rank, not a probability.

NVD base score

8.8 (CVSS v3.x), scored by the NVD independently of the CNA.

NVD CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

NVD analysis status

Modified. NVD last modified this record on 2026-10-08.

Red Hat severity

Low. Red Hat's rating for its own products, not a CVSS rating.

Exploit-prediction scores from FIRST. Independent scoring and analysis status from the NVD. Vendor severity from Red Hat. Exploitation assessment and catalog membership from CISA.

Published

2017-05-23 03:56Z9 YR AGO

Last updated

2026-10-08 21:24Z20 DAYS AGO

Reserved

2016-12-05

Assigning CNA

microfocus

Record state

PUBLISHED

Severity

Not rated by the issuing CNA

CNA CVSS vector

Not published by the issuing CNA

Weaknesses

• CWE-125Out-of-bounds ReadBase

Data version

5.2

Document digest

acc93497dd54686417b52e2252135c6df0a5303ce61316490935e988016fc07a

• access.redhat.comRHSA-2017:1221https://access.redhat.com/errata/RHSA-2017:1221vendor-advisoryx_refsource_REDHAT
• access.redhat.comRHSA-2017:1220https://access.redhat.com/errata/RHSA-2017:1220vendor-advisoryx_refsource_REDHAT
• access.redhat.comRHSA-2017:3047https://access.redhat.com/errata/RHSA-2017:3047vendor-advisoryx_refsource_REDHAT
• www.openwall.com[oss-security] 20161205 Re: CVE Request: zlib security issues found during audithttp://www.openwall.com/lists/oss-security/2016/12/05/21mailing-listx_refsource_MLIST
• www.securityfocus.com95131http://www.securityfocus.com/bid/95131vdb-entryx_refsource_BID
• access.redhat.comRHSA-2017:3046https://access.redhat.com/errata/RHSA-2017:3046vendor-advisoryx_refsource_REDHAT
• lists.opensuse.orgopenSUSE-SU-2017:0077http://lists.opensuse.org/opensuse-updates/2017-01/msg00050.htmlvendor-advisoryx_refsource_SUSE
• security.gentoo.orgGLSA-201701-56https://security.gentoo.org/glsa/201701-56vendor-advisoryx_refsource_GENTOO
• www.securitytracker.com1039427http://www.securitytracker.com/id/1039427vdb-entryx_refsource_SECTRACK
• access.redhat.comRHSA-2017:1222https://access.redhat.com/errata/RHSA-2017:1222vendor-advisoryx_refsource_REDHAT
• lists.opensuse.orgopenSUSE-SU-2017:0080http://lists.opensuse.org/opensuse-updates/2017-01/msg00053.htmlvendor-advisoryx_refsource_SUSE
• access.redhat.comRHSA-2017:3453https://access.redhat.com/errata/RHSA-2017:3453vendor-advisoryx_refsource_REDHAT
• lists.opensuse.orgopenSUSE-SU-2016:3202http://lists.opensuse.org/opensuse-updates/2016-12/msg00127.htmlvendor-advisoryx_refsource_SUSE
• access.redhat.comRHSA-2017:2999https://access.redhat.com/errata/RHSA-2017:2999vendor-advisoryx_refsource_REDHAT
• lists.debian.org[debian-lts-announce] 20190324 [SECURITY] [DLA 1725-1] rsync security updatehttps://lists.debian.org/debian-lts-announce/2019/03/msg00027.htmlmailing-listx_refsource_MLIST
• usn.ubuntu.comUSN-4246-1https://usn.ubuntu.com/4246-1/vendor-advisoryx_refsource_UBUNTU
• lists.debian.org[debian-lts-announce] 20200129 [SECURITY] [DLA 2085-1] zlib security updatehttps://lists.debian.org/debian-lts-announce/2020/01/msg00030.htmlmailing-listx_refsource_MLIST
• usn.ubuntu.comUSN-4292-1https://usn.ubuntu.com/4292-1/vendor-advisoryx_refsource_UBUNTU
• www.oracle.comhttp://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.htmlx_refsource_CONFIRM
• www.oracle.comhttps://www.oracle.com/security-alerts/cpujul2020.htmlx_refsource_MISC
• www.oracle.comhttp://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.htmlx_refsource_CONFIRM
• support.apple.comhttps://support.apple.com/HT208144x_refsource_CONFIRM
• github.comhttps://github.com/madler/zlib/commit/6a043145ca6e9c55184013841a67b2fef87e44c0x_refsource_CONFIRM
• wiki.mozilla.orghttps://wiki.mozilla.org/MOSS/Secure_Open_Source/Completed#zlibx_refsource_MISC
• bugzilla.redhat.comhttps://bugzilla.redhat.com/show_bug.cgi?id=1402345x_refsource_CONFIRM
• support.apple.comhttps://support.apple.com/HT208113x_refsource_CONFIRM
• support.apple.comhttps://support.apple.com/HT208112x_refsource_CONFIRM
• support.apple.comhttps://support.apple.com/HT208115x_refsource_CONFIRM
• wiki.mozilla.orghttps://wiki.mozilla.org/images/0/09/Zlib-report.pdfx_refsource_MISC
• security.gentoo.orgGLSA-202007-54https://security.gentoo.org/glsa/202007-54vendor-advisoryx_refsource_GENTOO
• cert-portal.siemens.comhttps://cert-portal.siemens.com/productcert/html/ssa-470355.html