CVE-2002-0640

What it is

Buffer overflow in sshd in OpenSSH 2.3.1 through 3.3 may allow remote attackers to execute arbitrary code via a large number of responses during challenge response authentication when OpenBSD is using PAM modules with interactive keyboard authentication (PAMAuthenticationViaKbdInt).

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of data exposure, data tampering, service disruption.

Exploit odds

28.2% chance of exploitation in the next 30 days (EPSS). Higher than most.

Fix

No patch or advisory is linked yet. Look at mitigations or restrict exposure.

Timeline

1. 2002-07-03 04:00 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-06-16 21:57 UTC Last updatedMost recent change to the record

Why it ranks here

• Exploited in the wild: no, CISA does not list it.
• Exploit odds: 28.2% in the next 30 days (EPSS).
• Severity: 10.0 HIGH (CVSS).
• Fix: none linked yet, which raises it.

Details

Published

2002-07-03 04:00 UTC

Last modified

2026-06-16 21:57 UTC

Exploit probability

28.2% · EPSS, next 30 days

Record status

Modified

Affected

• Openbsd OpenSSH 1.2.2
• Openbsd OpenSSH 1.2.3
• Openbsd OpenSSH 2.1
• Openbsd OpenSSH 2.1.1
• Openbsd OpenSSH 2.2
• Openbsd OpenSSH 2.3
• Openbsd OpenSSH 2.5
• Openbsd OpenSSH 2.5.1

Attack profile CVSS 2.0 · 10.0

Attack vector

Network

Complexity

Low

Authentication

None

Confidentiality

Complete

Integrity

Complete

Availability

Complete

Is it in your code?

Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.

Read https://cve-list.com/agent/cve/CVE-2002-0640.md and follow it. Check whether this project is affected by CVE-2002-0640. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.

Copy as ticket · More options · Status badge