# Go JOSE: Panics in JSON parsing

Advisory record · `GHSA-vvm8-gf78-28g4`

- **Identifiers:** `GHSA-vvm8-gf78-28g4` · `CVE-2026-116586`
- **State:** Confirmed
- **Severity:** CVSS 6.9 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-674](https://cwe.mitre.org/data/definitions/674.html)
- **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md)
- **Published:** 28 Oct 2026
- **Updated:** 28 Oct 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 28 Oct 2026, 21:14 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `github.com/go-jose/go-jose/v4` (Go): affected `<4.1.5`; fixed in `4.1.5`
- `github.com/go-jose/go-jose/v3` (Go): affected `<=3.0.5`; no fixed version yet

## Machine-written summary

Summary written by Claude Haiku from the source advisory. Not reviewed by a person.

> The github.com/go-jose/go-jose/v4 package before 4.1.5 and github.com/go-jose/go-jose/v3 at or below 3.0.5 are affected. Parsing deeply nested JSON from untrusted input can exhaust the stack and crash the application. Upgrade v4 to 4.1.5; no fixed v3 version is listed, so reject large inputs before parsing.

Written 1 Nov 2026.

## Not analysed yet

We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check.

## Severity and exploitation

- 6.9 Medium, CVSS 4.0: `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`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0029, the 21st percentile, on 5 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:11 UTC: First seen by agentprime
- 31 Oct 2026, 14:11 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-vvm8-gf78-28g4)

## Sources

- [GitHub Advisory Database: GHSA-vvm8-gf78-28g4](https://github.com/advisories/GHSA-vvm8-gf78-28g4)
- [OSV: GHSA-vvm8-gf78-28g4](https://osv.dev/vulnerability/GHSA-vvm8-gf78-28g4)
- <https://github.com/go-jose/go-jose/security/advisories/GHSA-vvm8-gf78-28g4>
- <https://nvd.nist.gov/vuln/detail/CVE-2026-116586>
- <https://github.com/go-jose/go-jose/pull/290>
- <https://github.com/go-jose/go-jose/commit/a31af25836222f4c45d366d6e8f9b1049dd9935a>
- <https://github.com/go-jose/go-jose>
- <https://github.com/go-jose/go-jose/releases/tag/v4.1.5>

Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code.

## Check whether this affects you

A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet.

- With the agentprime MCP server (<https://api.agentprime.io/mcp>), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: <https://agentprime.io/mcp.md>
- In a browser: <https://agentprime.io/check/> reads your lockfile in the browser, never uploading it.
- Whether it touches your code, with file and line: the Claude Code plugin, <https://agentprime.io/plugin.md>
- As JSON: <https://api.agentprime.io/v1/advisories/GHSA-vvm8-gf78-28g4>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

---

The web page: <https://agentprime.io/advisories/GHSA-vvm8-gf78-28g4/>. Everything for agents: <https://agentprime.io/llms.txt>.