Vulnerability in Golang Crypto
CVE-2026-42508
Previously, a revoked 'SignatureKey' belonging to a CA was not correctly checked for revocation. Now, both the 'key' and 'key.SignatureKey' are checked for @revoked.
Vulnerability class: Improper Certificate Validation
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.1 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.007 (50.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 50th percentile — 50.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.073 · newest: 0.007 · change: -0.067
Affected products
Weakness classification (CWE)
References
- go.dev/issue/79568 (Issue Tracking)
- go.dev/cl/781220 (Issue Tracking)
- groups.google.com/g/golang-announce/c/a082jnz-LvI (Mailing List)
- pkg.go.dev/vuln/GO-2026-5021 (Vendor Advisory)
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c
Frequently asked questions
- What is CVE-2026-42508?
- CVE-2026-42508 is a critical-severity vulnerability in Golang Crypto, classified under Improper Certificate Validation. CVSS score: 9.1/10. Published 2026-05-22.
- How severe is CVE-2026-42508?
- Critical severity. CVSS v3 base score is 9.1 out of 10.