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Fencer Vulns
high 7.5

CVE-2018-0732 in the critical feed json

Client DoS due to large DH parameter

published 2018-06-12 8 y ago modified 2026-10-08 31 d ago also EUVD-2018-1542

cvss
7.5
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
47.0%
EPSS 47.0% chance of exploitation in 30 days, percentile 98%
public exploits
0
none known

Summary

During key agreement in a TLS handshake using a DH(E) based ciphersuite a malicious server can send a very large prime value to the client. This will cause the client to spend an unreasonably long period of time generating a key for this prime resulting in a hang until the client has finished. This could be exploited in a Denial Of Service attack. Fixed in OpenSSL 1.1.0i-dev (Affected 1.1.0-1.1.0h). Fixed in OpenSSL 1.0.2p-dev (Affected 1.0.2-1.0.2o).

Patch / fix

  • nodejs node.js 6.8.1, 6.14.4, 8.8.1, 8.11.4, 10.9.0
  • openssl Debian 14, Debian 13, Debian 12 1.1.1-1

debian advisories DEBIAN-CVE-2018-0732

  • openssl Ubuntu 14.04 LTS 1.0.1f-1ubuntu2.26
  • openssl Ubuntu 16.04 LTS 1.0.2g-1ubuntu4.13
  • openssl Ubuntu 18.04 LTS 1.1.0g-2ubuntu4.1
  • openssl1.0 Ubuntu 18.04 LTS 1.0.2n-1ubuntu5.1

ubuntu advisories UBUNTU-CVE-2018-0732

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssl RHEL 7 1:1.0.2k-16.el7
  • openssl-libs RHEL 7 1:1.0.2k-16.el7
  • openssl-perl RHEL 7 1:1.0.2k-16.el7
  • jbcs-httpd24-httpd jboss core services 1 2.4.29-40.jbcs.el6
  • jbcs-httpd24-httpd jboss core services 1 2.4.29-40.jbcs.el7
  • jbcs-httpd24-mod_ssl jboss core services 1 1:2.4.29-40.jbcs.el6
  • jbcs-httpd24-mod_ssl jboss core services 1 1:2.4.29-40.jbcs.el7
  • jbcs-httpd24-openssl jboss core services 1 1:1.0.2n-15.jbcs.el6

red hat advisories RHSA-2018:3221RHSA-2019:1297RHSA-2018:2553RHSA-2018:2552

  • openssl SLES 12 SP3, SLES 12 SP2-BCL, SLED 12 SP3 +6 more 1.0.2j-60.30.1
  • openssl-1_0_0 SLE Module for Legacy 15 1.0.2p-3.8.1
  • openssl-1_1 SLE Module for Basesystem 15 1.1.0i-4.9.2
  • openssl SLE Module for Basesystem 15 1.1.0i-3.3.1
  • nodejs8 SLE Module for Web and Scripting 15 8.11.4-3.8.2
  • nodejs6 SLE Module for Web and Scripting 12, OpenStack Cloud Crowbar 8, OpenStack Cloud 7 +1 more 6.14.4-11.18.1
  • compat-openssl098 SLES for SAP 12 SP3, SLES for SAP 12 SP2, SLES for SAP 12 SP1 +2 more 0.9.8j-106.6.1
  • nodejs4 SLE Module for Web and Scripting 12, Enterprise Storage 4 4.9.1-15.14.1

suse advisories SUSE-SU-2019:14246-1SUSE-SU-2019:1553-1SUSE-SU-2018:1887-2SUSE-SU-2018:2965-1SUSE-SU-2018:2956-1SUSE-SU-2018:2812-1

  • openssl-1_0_0 openSUSE Tumbleweed 1.0.2u-6.2
  • openssl-1_1 openSUSE Tumbleweed 1.1.1l-1.2
  • virtualbox openSUSE Tumbleweed 6.1.26-3.2

opensuse advisories openSUSE-SU-2024:11126-1openSUSE-SU-2024:11127-1openSUSE-SU-2024:11501-1

  • openssl Alpine 3.8, Alpine 3.7, Alpine 3.6 +3 more 1.0.2o-r1
  • libressl Alpine 3.24, Alpine 3.23, Alpine 3.22 +14 more 2.7.4-r0
  • libressl Alpine 3.7 2.6.5-r0

alpine advisories ALPINE-CVE-2018-0732

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • openssl Arch Linux 1.1.0.i-1
  • lib32-openssl Arch Linux 1:1.1.0.i-1

arch linux advisories AVG-674AVG-675

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2018-0732 updated cvss 4.3

openssl: Malicious server can send large prime to client during DH(E) TLS handshake causing the client to hang

  • Red Hat Enterprise Linux 5 openssl, openssl097a Red Hat Enterprise Linux 6 openssl, openssl098e, openssl-perl Red Hat Enterprise Linux 7 OVMF, openssl098e
    affected: no fix planned “Will not fix”
  • Red Hat JBoss Enterprise Application Platform 5 openssl
    affected: no fix planned “Out of support scope”
  • Red Hat JBoss Enterprise Application Platform 6 openssl Red Hat JBoss Enterprise Web Server 2 openssl
    affected: no fix planned “Will not fix”
  • Red Hat JBoss Web Server 3 openssl
    affected: no fix available
  • Red Hat JBoss Core Services Apache HTTP Server 2.4.29 SP2
    fixed: vendor fix RHSA-2019:1543
  • Red Hat Enterprise Linux Client (v. 7) openssl 1.0.2k-16.el7, openssl-libs 1.0.2k-16.el7 Red Hat Enterprise Linux Client Optional (v. 7) openssl-perl 1.0.2k-16.el7 Red Hat Enterprise Linux ComputeNode (v. 7) openssl 1.0.2k-16.el7, openssl-libs 1.0.2k-16.el7 Red Hat Enterprise Linux ComputeNode Optional (v. 7) openssl-perl 1.0.2k-16.el7 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) openssl 1.0.2k-16.el7, openssl-libs 1.0.2k-16.el7 Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) openssl-perl 1.0.2k-16.el7
    +4 more products
    Red Hat Enterprise Linux Server (v. 7) openssl 1.0.2k-16.el7, openssl-libs 1.0.2k-16.el7 Red Hat Enterprise Linux Server Optional (v. 7) openssl-perl 1.0.2k-16.el7 Red Hat Enterprise Linux Workstation (v. 7) openssl 1.0.2k-16.el7, openssl-libs 1.0.2k-16.el7 Red Hat Enterprise Linux Workstation Optional (v. 7) openssl-perl 1.0.2k-16.el7
    fixed: vendor fix RHSA-2018:3221
  • Red Hat JBoss Core Services on RHEL 6 Server jbcs-httpd24-httpd 2.4.29-40.jbcs.el6, jbcs-httpd24-mod_ssl 2.4.29-40.jbcs.el6, jbcs-httpd24-openssl 1.0.2n-15.jbcs.el6, jbcs-httpd24-mod_ldap 2.4.29-40.jbcs.el6, jbcs-httpd24-httpd-tools 2.4.29-40.jbcs.el6, jbcs-httpd24-mod_session 2.4.29-40.jbcs.el6, +5 more Red Hat JBoss Core Services on RHEL 7 Server jbcs-httpd24-httpd 2.4.29-40.jbcs.el7, jbcs-httpd24-mod_ssl 2.4.29-40.jbcs.el7, jbcs-httpd24-openssl 1.0.2n-15.jbcs.el7, jbcs-httpd24-mod_ldap 2.4.29-40.jbcs.el7, jbcs-httpd24-httpd-tools 2.4.29-40.jbcs.el7, jbcs-httpd24-mod_session 2.4.29-40.jbcs.el7, +5 more
    fixed: vendor fix RHSA-2019:1297
  • Red Hat OpenShift Application Runtimes Node.js 8 npm 5.6.0-1.8.11.4.2.el7, rhoar-nodejs 8.11.4-2.el7
    fixed: vendor fix RHSA-2018:2552
show 2 more
  • Red Hat OpenShift Application Runtimes Node.js 10 npm 6.2.0-1.10.9.0.1.el7, rhoar-nodejs 10.9.0-1.el7
    fixed: vendor fix RHSA-2018:2553
  • Red Hat Enterprise Linux 8 openssl, openssl-libs, openssl-perl
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-21-159-08 updated cvss 7.5

Siemens TIM 1531 IRC

Facts from CISA's republication of the vendor's own advisory (CSAF); the linked advisory is the authoritative source. CISA notification · csaf

CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
31 d ago

Exploit prediction

47.01% chance of exploitation in the next 30 days, higher than 98% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD 2.0 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P

Affected products

  • OpenSSL OpenSSL

Classification

Weakness
Technology feeds

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.