Vulnerability · Published Apr 14, 2021 · Assigned by mitre

CVE-2021-28484

High 7.5

In plain English

A high-severity security flaw in the github.com/Yubico/yubihsm-connector package (Go). There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.5% (higher than 75% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS NVD)7.5High

Exploit odds (30 days)1.5%top 25.3% of all CVEs

Exploited in the wildNo reportsnot in CISA KEV

Attack toolingNoneno public tooling known

Official 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.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Go	github.com/Yubico/yubihsm-connector	3.0.1	GHSA-8m9g-647g-5pxw

Affected products (as reported)

Vendor	Product	Versions
n/a	n/a	n/a

References

https://github.com/Yubico/yubihsm-connector/releases x_refsource_MISC
https://www.yubico.com/support/security-advisories/ysa-2021-02/ x_refsource_MISC
FEDORA-2021-d04010b90e vendor-advisory, x_refsource_FEDORA