CVE-2021-28484: High severity yubico yubihsm connector vulnerability

Published Apr 14, 2021
·
Updated

An issue was discovered in the /api/connector endpoint handler in Yubico yubihsm-connector before 3.0.1 (in YubiHSM SDK before 2021.04). The handler did not validate the length of the request, which can lead to a state where yubihsm-connector becomes stuck in a loop waiting for the YubiHSM to send it data, preventing any further operations until the yubihsm-connector is restarted. An attacker can send 0, 1, or 2 bytes to trigger this.

Affected Software

2 affected components
Yubico Yubihsm Connector<3.0.1
Fedoraproject Fedora=34

Event History

Apr 14, 2021
CVE Published
via MITRE·05:07 PM
Data Sourced
via MITRE·05:07 PM
Description
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Frequently Asked Questions

1

What is the vulnerability ID for this issue?

The vulnerability ID for this issue is CVE-2021-28484.

2

What is the affected software?

The affected software is Yubico Yubihsm Connector version up to and excluding 3.0.1.

3

What is the severity of CVE-2021-28484?

The severity of CVE-2021-28484 is high.

4

How can this vulnerability be exploited?

This vulnerability can be exploited by sending a request of invalid length to the /api/connector endpoint in Yubico yubihsm-connector.

5

Are there any references related to this vulnerability?

Yes, you can find references related to this vulnerability at the following links: [GitHub](https://github.com/Yubico/yubihsm-connector/releases), [Fedora Project](https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/B7Q2KGXSPQEEONAWMFZRVH2TXWX3QPCQ/), [Yubico](https://www.yubico.com/support/security-advisories/ysa-2021-02/).

Contact

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