CVE-2018-0732

Client DoS due to large DH parameter

HIGH

7.5

CVSS Score

Published: June 12, 2018 at 01:00 PM UTC

Updated: October 8, 2026 at 10:16 PM UTC

4 products affected across 4 vendorsDebian LinuxUbuntu LinuxOpenSSL

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Severity

HIGH7.5

Exploit prediction

EPSS 47%

SSVC

No known exploit

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).

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Ubuntu Linux · Canonicalrubygems

95%

12.04 14.04 16.04 17.10 18.04

Debian Linux · Debiandrupal

95%

8.0

Node.js · Node.js

95%

10.0.0 ≤ v < 10.9.06.0.0 ≤ v < 6.8.16.9.0 ≤ v < 6.14.48.0.0 ≤ v < 8.8.18.9.0 ≤ v < 8.11.4*

Affected range stops below 10.9.0, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.14.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 6.8.1, so it looks safe — our inference, not a vendor statement

Affected range stops below 8.11.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 8.8.1, so it looks safe — our inference, not a vendor statement

OpenSSL · OpenSSL

95%

1.0.2 ≤ v ≤ 1.0.2o1.1.0 ≤ v ≤ 1.1.0h*Fixed in OpenSSL 1.0.2p-dev (Affected 1.0.2-1.0.2o)Fixed in OpenSSL 1.1.0i-dev (Affected 1.1.0-1.1.0h)

Vendor states this is fixed in 1.0.2p-dev (unaffected)

Vendor states this is fixed in 1.1.0i-dev (unaffected)

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

References (37)

x_refsource_CONFIRMPatchThird Party Advisory

Source: [email protected]

http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html

VDB Entryx_refsource_BIDThird Party Advisory

Source: [email protected]

http://www.securityfocus.com/bid/104442

VDB Entryx_refsource_SECTRACKThird Party Advisory

Source: [email protected]

http://www.securitytracker.com/id/1041090