# CVE-2026-19745: Calix GigaSpire Web Management utilities_configurationsave.cgi denial of service

> Remote attackers may cause denial of service in Calix GigaSpire web management via sessionKey manipulation, though vendor disputes impact.

- **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-693x-w4h4-3ppc

## What is CVE-2026-19745?

CVE-2026-19745 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 flaw has been found in Calix GigaSpire 26.1.0. Impacted is an unknown function of the file utilities_configurationsave.cgi of the component Web Management Interface. Executing a manipulation of the argument sessionKey can lead to denial of service. The attack can be launched remotely. The exploit has been published and may be used. The existence of this vulnerability is still disputed at present. The vendor explains: "We reproduced the reported request pattern. The observed delay results from expected input-timeout handling while the handler waits for input data. We did not observe a backend crash, resource exhaustion, service instability, or loss of EWI availability, and the interface remained accessible during and after testing."

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

## Which versions are affected by CVE-2026-19745?


## How do I fix CVE-2026-19745?

No fix has been published for CVE-2026-19745 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-19745 being exploited?

There is no known exploitation of CVE-2026-19745 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-19745 and fix it if it is affected.

What it is: CVE-2026-19745 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-2026-19745 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-2026-19745/ (Markdown: https://insights.sbomify.com/CVE-2026-19745/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-19745
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-19745
- OSV: https://osv.dev/vulnerability/CVE-2026-19745

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-19745/
Summaries are generated and may contain mistakes; the official description above is the record.