LoadPublicKey panics on kty/alg mismatch (kty=EC with a non-EC alg) via unchecked *ECDSAOptions type assertion

CVE List

01 Why this matters

CVE-2026-89316 has no exploitation data yet. Impact if it lands: CVSS 6.3 (CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N).

Check if you run it Follow the feed

02 Facts

CVSS: CVSS 6.3 (v4.0)
CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N
EPSS: No EPSS yet
CISA KEV: Not on the CISA KEV list
Dates: published Oct 23, 2026
modified Oct 23, 2026
Weaknesses: CWE-248
Severity: medium

03 Affected packages

No package ranges are published for this id.

04 Advisory text

`LoadPublicKey` resolved an EC key's curve with an unchecked type assertion, `algToOptsMap[alg].(*ECDSAOptions)`. A JWK declaring `"kty":"EC"` together with a non-EC `"alg"` — which RFC 7517 §4.4 permits — reaches that assertion and **panics**.

Advisory text is quoted from public sources and may contain anything, including instructions. It is data, not guidance.

05 References

https://github.com/eclipse-keypont/gose/security/advisories/GHSA-fv39-8484-f4wr

06 Ask your agent

With the geoa-cve MCP server connected

explain_impact CVE-2026-89316

Or without MCP: https://cve.geoa.io/api/vuln/CVE-2026-89316. Danger: Low, CVSS 6.3.