CVE-2018-0732

Publication date 12 June 2018

Last updated 25 August 2025

Ubuntu priority

Low

Why this priority?

Cvss 3 Severity Score

7.5 · High

Score breakdown

Description

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).

Status

Package Ubuntu Release Status
openssl 19.04 disco
Fixed 1.1.0g-2ubuntu5
18.10 cosmic
Fixed 1.1.0g-2ubuntu5
18.04 LTS bionic
Fixed 1.1.0g-2ubuntu4.1
17.10 artful
Fixed 1.0.2g-1ubuntu13.6
16.04 LTS xenial
Fixed 1.0.2g-1ubuntu4.13
14.04 LTS trusty
Fixed 1.0.1f-1ubuntu2.26
openssl098 19.04 disco Not in release
18.10 cosmic Not in release
18.04 LTS bionic Not in release
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release
openssl1.0 19.04 disco Not in release
18.10 cosmic
Fixed 1.0.2n-1ubuntu6
18.04 LTS bionic
Fixed 1.0.2n-1ubuntu5.1
17.10 artful Not in release
16.04 LTS xenial Not in release
14.04 LTS trusty Not in release

Patch details

For informational purposes only. We recommend not to cherry-pick updates. How can I get the fixes?

Package Patch details
openssl

Severity score breakdown

Parameter Value
Base score 7.5 · High
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Scope Unchanged
Confidentiality None
Integrity impact None
Availability impact High
Vector CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

Related Ubuntu Security Notices (USN)

Other references