# nebula-mesh: Unauthenticated OIDC login endpoint allocates unbounded in-memory state entries without rate limiting

Advisory record · `GHSA-m3cx-mwpg-32jg`

- **Identifiers:** `GHSA-m3cx-mwpg-32jg` · `CVE-2026-55512` · `GO-2026-5989`
- **State:** Confirmed
- **Severity:** CVSS 5.3 Medium
- **Critical:** No
- **Weakness (CWE):** [CWE-400](https://cwe.mitre.org/data/definitions/400.html)
- **Tags:** [Denial of service](https://agentprime.io/advisories/tag/dos.md)
- **Published:** 14 Jul 2026
- **Updated:** 23 Jul 2026
- **Reviewed by a person:** No

Published by the GitHub Advisory Database at 14 Jul 2026, 20:19 UTC. agentprime has not analysed this yet, so whether it affects any app is not known.

## Affected packages

- `github.com/forgekeep/nebula-mesh` (Go): affected `>=0.2.0, <0.5.0`; fixed in `0.5.0`

## Machine-written summary

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

> Versions 0.2.0 up to but not including 0.5.0 of the Go module github.com/forgekeep/nebula-mesh are affected. When OIDC is enabled, the unauthenticated /ui/oidc/login endpoint stores a new in-memory state entry on every request, and these entries are not rate-limited or capped in number. A remote attacker with network access can repeatedly send requests to grow server memory for the ten-minute state lifetime, which risks availability degradation. Upgrade to version 0.5.0. The source does not list a workaround.

Written 6 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

- 5.3 Medium, CVSS 3.1: `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L`, from CNA (GitHub_M)

- **CISA KEV:** Not listed.
- **EPSS:** 0.0060, the 49th percentile, on 15 Nov 2026: FIRST’s estimate of the chance of exploitation in the next 30 days.

## Timeline

- 31 Oct 2026, 14:57 UTC: First seen by agentprime
- 31 Oct 2026, 14:57 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/GHSA-m3cx-mwpg-32jg)

## Sources

- [GitHub Advisory Database: GHSA-m3cx-mwpg-32jg](https://github.com/advisories/GHSA-m3cx-mwpg-32jg)
- [OSV: GHSA-m3cx-mwpg-32jg](https://osv.dev/vulnerability/GHSA-m3cx-mwpg-32jg)
- <https://github.com/forgekeep/nebula-mesh/security/advisories/GHSA-m3cx-mwpg-32jg>
- <https://github.com/forgekeep/nebula-mesh/commit/bc387086cc0e4b9c1654468b7391af19cacfe367>
- <https://github.com/forgekeep/nebula-mesh>
- <https://github.com/forgekeep/nebula-mesh/releases/tag/v0.5.0>

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-m3cx-mwpg-32jg>, or `POST https://api.agentprime.io/v1/match` with your packages (<https://agentprime.io/api.md>)

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The web page: <https://agentprime.io/advisories/GHSA-m3cx-mwpg-32jg/>. Everything for agents: <https://agentprime.io/llms.txt>.