CVE-2021-28484: 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…

PriorityP339high7.5CVSS 3.1

AVNACLPRNUINSUCNINAH

EPSS

1.52%

71.8th percentile

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

3 ranges

Vendor	Product	Version range	Fixed in
fedoraproject	fedora	—	—
github.com	yubico_yubihsm-connector	>= 0 < 3.0.1	3.0.1
yubico	yubihsm_connector	< 3.0.1	3.0.1

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

nvdv2.05.0MEDIUMAV:N/AC:L/Au:N/C:N/I:N/A:P

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