# CVE-2026-33281: Ella Core panics on invalid PDU Session IDs in NGAP messages

> An attacker can crash the Ella Core 5G network service by sending crafted NGAP messages with invalid PDU Session IDs, disrupting connectivity for all subscribers.

- **Severity:** Medium 6.5 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 23 Mar 2026
- **Updated:** 24 Mar 2026
- **Also known as:** GHSA-q669-4gmv-g8mf, GO-2026-4783

## What is CVE-2026-33281?

CVE-2026-33281 is a medium-severity denial of service vulnerability in ellanetworks core, published on 23 Mar 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

Ella Core is a 5G core designed for private networks. Versions prior to 1.6.0 panic when processing NGAP messages with invalid PDU Session IDs outside of 1-15. An attacker able to send crafted NGAP messages to Ella Core can crash the process, causing service disruption for all connected subscribers. No authentication is required. Version 1.6.0 added PDU Session ID validations during NGAP message handling.

Weakness: CWE-129 (Improper Validation of Array Index)

## Which versions are affected by CVE-2026-33281?

3 open source packages ship an affected version, including github.com/ellanetworks/core. It affects 1 product.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `github.com/ellanetworks/core` | Go | All versions | 1.6.0 |
| `github.com/ellanetworks/core` | Go | All versions | 1.6.0 |
| `github.com/ellanetworks/core` | Go | All versions | 1.6.0 |

Products: Ellanetworks Ella Core.

## How do I fix CVE-2026-33281?

Upgrade github.com/ellanetworks/core to 1.6.0 or later.

## Is CVE-2026-33281 being exploited?

There is no known exploitation of CVE-2026-33281 in the wild and no public exploit code.

## Other vulnerabilities in ellanetworks core

- [CVE-2026-33282](https://insights.sbomify.com/CVE-2026-33282/): Ella Core panics on malformed NGAP Location Report (high 7.5)
- [CVE-2026-32319](https://insights.sbomify.com/CVE-2026-32319/): Ella Core: Unauthenticated AMF DoS via malformed InitialUEMessage with undersized integrity-protected NAS payload (high 7.5)
- [CVE-2026-33906](https://insights.sbomify.com/CVE-2026-33906/): Ella Core has Privilege Escalation via Database Restore by NetworkManager role (high 7.2)
- [CVE-2026-33903](https://insights.sbomify.com/CVE-2026-33903/): Ella Core panics when processing a crafted NGAP LocationReport message (medium 6.5)
- [CVE-2026-33904](https://insights.sbomify.com/CVE-2026-33904/): Ella Core has a Denial of Service via SCTP connection cleanup deadlock (medium 6.5)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-33281 and fix it if it is affected.

What it is: CVE-2026-33281 is a medium-severity denial of service vulnerability in ellanetworks core, published on 23 Mar 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-2026-33281 in the wild and no public exploit code.

Affected packages and fixed versions:
- github.com/ellanetworks/core (Go): affected all versions; fixed in 1.6.0
- github.com/ellanetworks/core (Go): affected all versions; fixed in 1.6.0
- github.com/ellanetworks/core (Go): affected all versions; fixed in 1.6.0

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-2026-33281/ (Markdown: https://insights.sbomify.com/CVE-2026-33281/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-33281
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-33281
- OSV: https://osv.dev/vulnerability/CVE-2026-33281

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-33281/
Summaries are generated and may contain mistakes; the official description above is the record.