Denial of Service Vulnerability in Go's Crypto/X509 and Crypto/TLS
CVE-2026-32280

7.5HIGH

Key Information:

Vendor

Go Standard Library

Status
Crypto/x509
Vendor
CVE Published:
8 April 2026

What is CVE-2026-32280?

A flaw in the Go programming language's crypto/x509 and crypto/tls libraries allows for denial of service during chain building processes. This issue arises when an excessive number of intermediate certificates are supplied, leading to insufficient work limitation in VerifyOptions.Intermediates. This could impact users relying on these libraries for secure communications, exposing them to significant downtimes.

Affected Version(s)

crypto/x509 0 < 1.25.9

crypto/x509 1.26.0-0 < 1.26.2

References

https://go.dev/cl/758320
https://go.dev/issue/78282
https://groups.google.com/g/golang-announce/c/0uYbvbPZRWU

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Jakub Ciolek - https://ciolek.dev
.