Description
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 products
golang: go
References10
- pkg.go.dev/vuln/GO-2026-4947 Vendor Advisory
- go.dev/cl/758320 Patch
- go.dev/issue/78282 Issue Tracking
- groups.google.com/g/golang-announce/c/0uYbvbPZRWU Mailing ListRelease Notes
- access.redhat.com/errata/RHSA-2026:10217
- access.redhat.com/errata/RHSA-2026:10219
- access.redhat.com/errata/RHSA-2026:10704
- access.redhat.com/errata/RHSA-2026:11507
- access.redhat.com/errata/RHSA-2026:11514
- access.redhat.com/errata/RHSA-2026:11688
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 1% percentile: 51 · as of 12 November 2026
- CWE
- CWE-770
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