Vulnerability record · CVE-2021-34558 · published 15 July 2021
CVE-2021-34558: Golang go improper certificate validation vulnerability
Golang · Go
The crypto/tls package of Go through 1.16.5 does not properly assert that the type of public key in an X.509 certificate matches the expected type when doing a RSA based key exchange, allowing a malicious TLS server to cause a TLS client to panic.
Description
The crypto/tls package of Go through 1.16.5 does not properly assert that the type of public key in an X.509 certificate matches the expected type when doing a RSA based key exchange, allowing a malicious TLS server to cause a TLS client to panic.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Affected products
6 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
Track CVE-2021-34558 inside VULONE
Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.
Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2021-34558), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
