high · 7.5 Patched

yopass Prometheus metrics middleware allows remote memory exhaustion through unbounded method labels

CVE-2026-107840 · GHSA-6r69-c6wg-7g8m · GO-2026-6720 · published 9 Oct 2026

How serious is it

  • Severity: high, CVSS score 7.5 out of 10.
  • No exploit prediction (EPSS) score yet.
  • Not on the CISA list of exploited vulnerabilities.
  • No public exploit in Exploit-DB.

Is your app affected by CVE-2026-107840?

Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.

Who is affected

  • github.com/jhaals/yopass (Go) < 0.0.0-20260727191436-61e31ead04a4

How to check

  1. Run go list -m github.com/jhaals/yopass in your project to see the installed version, including copies pulled in by other packages.
  2. Or paste your lockfile into the checker: it lists every package with a known vulnerability, this one included.

How to fix

Copies a prompt for Claude Code, Cursor or Codex: it checks your lockfiles for this and upgrades it.
  1. Upgrade github.com/jhaals/yopass to 0.0.0-20260727191436-61e31ead04a4 or later, commit the lockfile and redeploy.
  2. If a vulnerable version was live, check your logs and rotate the secrets that server could read.

The advisory

The Prometheus metrics middleware in pkg/server/server.go used r.Method directly as a label value on request counter and duration histogram metrics. Since the mux catch-all route matches any HTTP method, an unauthenticated attacker can send requests with arbitrary method strings (e.g. curl -X "M1" http://host/), each creating new counter and histogram time series in the Prometheus registry. The registry's internal maps never evict entries. An attacker issuing requests with unique method values causes monotonic memory growth until the process is OOM-killed. Additionally, /metrics scrape latency degrades proportionally, eventually timing out and blinding monitoring. Remediation: Upgrade to 14.7.0 or later, which clamps the method label to a fixed allowlist (GET, POST, PUT, DELETE, OPTIONS, HEAD, CONNECT, TRACE) and maps everything else to other.

Check your whole app

Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.

References

Merged from GitHub Advisory Database, OSV, NVD. Last updated 24 Oct 2026. All vulnerabilities · RSS · JSON

Get alerts for new exploited vulnerabilities