JweRsaKeyEncryptionDecryptorImpl.Decrypt panics on attacker-chosen IV length (stdlib GCM.Open reached without nonce-size check)

CVE List

01 Why this matters

CVE-2026-89318 has no exploitation data yet. Impact if it lands: CVSS 6.9 (CVSS:4.0/AV:N/AC:L/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 6.9 (v4.0)
CVSS:4.0/AV:N/AC:L/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

`JweRsaKeyEncryptionDecryptorImpl.Decrypt` passed the JWE's initialization vector to `cipher.AEAD.Open` without checking its length. The Go standard library **panics** rather than returning an error when a GCM nonce is not exactly `NonceSize()` bytes, so a JWE carrying a wrong-sized IV crashes the decrypting goroutine.

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-265w-83cm-777q

06 Ask your agent

With the geoa-cve MCP server connected

explain_impact CVE-2026-89318

Or without MCP: https://cve.geoa.io/api/vuln/CVE-2026-89318. Danger: Low, CVSS 6.9.