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Vulnerability Assessment

Impact

CVSS score of 9.8 (CRITICAL). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. EPSS exploitation probability: 13.49%.

Exploit ScenarioDerived

This vulnerability can be exploited remotely over the network. Successful exploitation could compromise the critical-severity affected system.

Emergency Immediate action required. Why: CRITICAL + active threat signals, no patch available.
No patch listed yet 13.5% exploitation probability (EPSS)

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AnalysisAI

inffast.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Epss exploitation probability 13.5% and no vendor patch available.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply vendor patches when available. Implement network segmentation and monitoring as interim mitigations.

Affects your stack

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Technical ContextAI · show details

inffast.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic. Affected products include: Zlib, Opensuse Leap, Opensuse, Debian Debian Linux, Canonical Ubuntu Linux.

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  • Exploit and PoC references, threat intelligence from 22 sources

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Severity by source

NVD PRIMARY 9.8 CRITICAL
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

DescriptionNVD

inffast.c in zlib 1.2.8 might allow context-dependent attackers to have unspecified impact by leveraging improper pointer arithmetic.

Threat Intelligence Overview

Threat Score
4.4/10
Composite threat intelligence
EPSS Score
13.5%
Top 6% exploitable
Threat Intel
1
1 source
Data Quality
6 sources
Confidence: High
NVD CVE.org EPSS CISA GitHub VulDB

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue
Severity CRITICAL
CISA KEV No
Public POC No
EPSS 13.5%
Patch available No
Active threat Yes
Deciding rule
CRITICAL + active threat signals, no patch available
What every action level means
Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.
Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.
This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.
This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.
Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

SSVC AssessmentENISA

SSVC Decision· derived
Scheduled
Exploitation· derived
None
System Exposure· derived
Open
Automatable· derived
Yes
Human Impact· derived
Medium

Priority Score

72
Low Medium High Critical
KEV: 0
EPSS: +13
CVSS: +49
PoC: 0
Weaponized: 0
Threat intel: +10
Gov advisory: 0

Attack Technique

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.

Affected Products (CPE)NVD

cpe:2.3:a:zlib:zlib:*:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:42.1:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:leap:42.2:*:*:*:*:*:*:*
cpe:2.3:o:opensuse:opensuse:13.2:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
cpe:2.3:a:oracle:database_server:18c:*:*:*:*:*:*:*
cpe:2.3:a:oracle:jdk:1.6.0:update161:*:*:*:*:*:*
cpe:2.3:a:oracle:jdk:1.7.0:update151:*:*:*:*:*:*
cpe:2.3:a:oracle:jdk:1.8.0:update144:*:*:*:*:*:*
cpe:2.3:a:oracle:jre:1.6.0:update161:*:*:*:*:*:*
cpe:2.3:a:oracle:jre:1.7.0:update151:*:*:*:*:*:*
cpe:2.3:a:oracle:jre:1.8.0:update144:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql:*:*:*:*:*:*:*:*
cpe:2.3:a:oracle:mysql:*:*:*:*:*:*:*:*
cpe:2.3:a:redhat:satellite:5.8:*:*:*:*:*:*:*
cpe:2.3:o:redhat:enterprise_linux_desktop:6.0:*:*:*:*:*:*:*
+ 42 more

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Threat IntelligenceMISP

CISA Advisories
Sources: CISA (public domain)

References

Advisories & patches
ADVISORY https://vuldb.com/vuln/101649 ADVISORY https://vuldb.com/vuln/108156 ADVISORY https://vuldb.com/vuln/108442 ADVISORY https://vuldb.com/vuln/108479 ADVISORY https://vuldb.com/vuln/108518 REF http://lists.opensuse.org/opensuse-updates/2016-12/msg00127.html REF http://lists.opensuse.org/opensuse-updates/2017-01/msg00050.html REF http://lists.opensuse.org/opensuse-updates/2017-01/msg00053.html REF http://www.openwall.com/lists/oss-security/2016/12/05/21 REF http://www.oracle.com/technetwork/security-advisory/cpujul2018-4258247.html REF http://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html REF http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html REF http://www.securityfocus.com/bid/95131 REF http://www.securitytracker.com/id/1039427 REF http://www.securitytracker.com/id/1039596 REF https://access.redhat.com/errata/RHSA-2017:1220 REF https://access.redhat.com/errata/RHSA-2017:1221 REF https://access.redhat.com/errata/RHSA-2017:1222 REF https://access.redhat.com/errata/RHSA-2017:2999 REF https://access.redhat.com/errata/RHSA-2017:3046 REF https://access.redhat.com/errata/RHSA-2017:3047 REF https://access.redhat.com/errata/RHSA-2017:3453 REF https://bugzilla.redhat.com/show_bug.cgi?id=1402346 REF https://cert-portal.siemens.com/productcert/html/ssa-470355.html REF https://github.com/madler/zlib/commit/9aaec95e82117c1cb0f9624264c3618fc380cecb REF https://lists.debian.org/debian-lts-announce/2019/03/msg00027.html REF https://lists.debian.org/debian-lts-announce/2020/01/msg00030.html REF https://security.gentoo.org/glsa/201701-56 REF https://security.gentoo.org/glsa/202007-54 REF https://security.netapp.com/advisory/ntap-20171019-0001/ REF https://support.apple.com/HT208112 REF https://support.apple.com/HT208113 REF https://support.apple.com/HT208115 REF https://support.apple.com/HT208144 REF https://usn.ubuntu.com/4246-1/ REF https://usn.ubuntu.com/4292-1/ REF https://wiki.mozilla.org/MOSS/Secure_Open_Source/Completed#zlib REF https://wiki.mozilla.org/images/0/09/Zlib-report.pdf REF https://www.oracle.com/security-alerts/cpujul2020.html

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