# CVE-2026-86698: Refresh tokens accepted as private repository credentials at the CDN

> Retained refresh tokens allow former members to read private packages and documentation after their access is revoked.

- **Severity:** Low 2.3 (`CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 22 Sep 2026
- **Updated:** 22 Sep 2026
- **Also known as:** EEF-CVE-2026-86698, GHSA-vmw7-7g2w-gw2f

## What is CVE-2026-86698?

CVE-2026-86698 is a low-severity authentication bypass vulnerability in hexpm, published on 22 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Insufficient Session Expiration vulnerability in OAuth token issuance in hexpm hexpm allows a user whose organization membership or session has ended to keep reading the organization's private packages and their documentation tarballs via a retained refresh token.

generate_refresh_token/4 in lib/hexpm/oauth/jwt.ex signs the refresh token with the same iss, aud and scope claims as the access token, so it carries the same repository:<org> scopes. The CDN service that serves private repositories verifies the signature and time claims and then authorizes from the scope claim, with no database lookup and no way to tell the two token kinds apart. Removing a member or revoking a session therefore takes effect at the CDN only when the 30 day refresh token expires, instead of after the 30 minute access token lifetime. Access is read-only and limited to organizations the account belonged to when the token was granted.

This issue affects hex.pm: from 2025-10-10 before 2026-09-22.

Weakness: CWE-613 (DEPRECATED: Insufficient Session Expiration)

## Which versions are affected by CVE-2026-86698?


## How do I fix CVE-2026-86698?

No fix has been published for CVE-2026-86698 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-86698 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86698 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-86698 and fix it if it is affected.

What it is: CVE-2026-86698 is a low-severity authentication bypass vulnerability in hexpm, published on 22 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-86698 exists.

Affected product: hexpm. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-86698/ (Markdown: https://insights.sbomify.com/CVE-2026-86698/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-86698
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-86698
- OSV: https://osv.dev/vulnerability/CVE-2026-86698

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-86698/
Summaries are generated and may contain mistakes; the official description above is the record.