CVE-2021-28484

Description

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.56%
Vendor Advisory fedoraproject.org Vendor Advisory yubico.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/Yubico/yubihsm-connector/releases third party advisory
https://www.yubico.com/support/security-advisories/ysa-2021-02/ vendor advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/B7Q2KGXSPQEEONAWMFZRVH2TXWX3QPCQ/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-28484?
CVE-2021-28484 has been scored as a high severity vulnerability.
How to fix CVE-2021-28484?
To fix CVE-2021-28484, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-28484 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-28484 is being actively exploited. According to its EPSS score, there is a ~1% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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