CVE-2026-32280 — Unexpected work during chain building in crypto/x509

Description (CNA)

During chain building, the amount of work that is done is not correctly limited when a large number of intermediate certificates are passed in VerifyOptions.Intermediates, which can lead to a denial of service. This affects both direct users of crypto/x509 and users of crypto/tls.

Affected (CNA)

Vendor / product	Versions
Go standard library / crypto/x509	affected 0 before 1.25.9; affected 1.26.0-0 before 1.26.2

CWE

No CWE identifiers supplied.

References

ADP enrichment

CISA-ADP

No English description supplied.

No references supplied.

redhat-SADP

A flaw was found in the Go standard library packages `crypto/x509` and `crypto/tls`. During the process of building a certificate chain, an attacker can provide a large number of intermediate certificates. This excessive input is not properly limited, leading to an uncontrolled amount of work being performed. This can result in a denial of service (DoS) condition, making the affected system or application unavailable to legitimate users.