# CVE-2026-67437: OliveTin: Unauthenticated DoS via OAuth2 State Memory Exhaustion (Unbounded Map Growth)

> Unauthenticated attackers can exhaust server memory by repeatedly triggering OAuth2 login requests, causing a denial of service in OliveTin.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 29 Jul 2026
- **Updated:** 30 Jul 2026
- **Also known as:** GHSA-xpxj-f2fm-rqch, GO-2026-6146

## What is CVE-2026-67437?

CVE-2026-67437 is a high-severity denial of service vulnerability in OliveTin, published on 29 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

OliveTin gives access to predefined shell commands from a web interface. From 3000.0.0 until 3000.17.0, the service/internal/auth/otoauth2/restapi_auth_oauth2.go OAuth2 login handler stores per-login state in the registeredStates map on every /oauth/login request without expiring, deleting, or bounding entries, allowing an unauthenticated attacker to exhaust memory and cause a denial of service. This issue is fixed in version 3000.17.0.

Weakness: CWE-770 (Allocation of Resources Without Limits or Throttling), CWE-401 (Missing Release of Memory after Effective Lifetime), CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-67437?

3 open source packages ship an affected version, including github.com/OliveTin/OliveTin.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/OliveTin/OliveTin` | Go | From 0.0.0-20251024001301-45f9c18bc3ee | 0.0.0-20260708075951-ec114e95d297 |
| `github.com/OliveTin/OliveTin` | Go | From 0.0.0-20251024001301-45f9c18bc3ee | 0.0.0-20260708075951-ec114e95d297 |
| `github.com/OliveTin/OliveTin` | Go | From 0.0.0-20251024001301-45f9c18bc3ee | 0.0.0-20260708075951-ec114e95d297 |

## How do I fix CVE-2026-67437?

Upgrade github.com/OliveTin/OliveTin to 0.0.0-20260708075951-ec114e95d297 or later.

## Is CVE-2026-67437 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-67437 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-67437 and fix it if it is affected.

What it is: CVE-2026-67437 is a high-severity denial of service vulnerability in OliveTin, published on 29 Jul 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-67437 exists.

Affected packages and fixed versions:
- github.com/OliveTin/OliveTin (Go): affected from 0.0.0-20251024001301-45f9c18bc3ee; fixed in 0.0.0-20260708075951-ec114e95d297
- github.com/OliveTin/OliveTin (Go): affected from 0.0.0-20251024001301-45f9c18bc3ee; fixed in 0.0.0-20260708075951-ec114e95d297
- github.com/OliveTin/OliveTin (Go): affected from 0.0.0-20251024001301-45f9c18bc3ee; fixed in 0.0.0-20260708075951-ec114e95d297

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-67437/ (Markdown: https://insights.sbomify.com/CVE-2026-67437/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-67437
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-67437
- OSV: https://osv.dev/vulnerability/CVE-2026-67437

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-67437/
Summaries are generated and may contain mistakes; the official description above is the record.