# CVE-2026-19746: Calix GigaSpire traceroute.cmd denial of service

> A remote attacker could potentially cause a denial of service in Calix GigaSpire devices via the traceroute command, though vendor testing did not reproduce the issue.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **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:** 13 Aug 2026
- **Updated:** 16 Oct 2026
- **Also known as:** GHSA-6w9r-x9gv-7c46

## What is CVE-2026-19746?

CVE-2026-19746 is a medium-severity denial of service vulnerability in Calix GigaSpire, published on 13 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability has been found in Calix GigaSpire 26.1.0. The affected element is an unknown function of the file traceroute.cmd. The manipulation leads to denial of service. The attack may be initiated remotely. The exploit has been disclosed to the public and may be used. The presence of this vulnerability remains uncertain at this time. The vendor explains: "After reviewing the researcher's videos, we repeated the test using his described setup: the traceroute cancel request was sent while a second client was connected to the EWI. The second client remained connected and was not interrupted, and we did not observe a forced logout, session invalidation, or loss of EWI availability."

Weakness: CWE-404 (Improper Resource Shutdown or Release)

## Which versions are affected by CVE-2026-19746?


## How do I fix CVE-2026-19746?

No fix has been published for CVE-2026-19746 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-19746 being exploited?

There is no known exploitation of CVE-2026-19746 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-19746 and fix it if it is affected.

What it is: CVE-2026-19746 is a medium-severity denial of service vulnerability in Calix GigaSpire, published on 13 Aug 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-19746 in the wild and no public exploit code.

Affected product: Calix GigaSpire. 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-2026-19746/ (Markdown: https://insights.sbomify.com/CVE-2026-19746/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-19746
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-19746
- OSV: https://osv.dev/vulnerability/CVE-2026-19746

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-19746/
Summaries are generated and may contain mistakes; the official description above is the record.