# CVE-2026-1522: Open5GS SGWC s5c-handler.c sgwc_s5c_handle_modify_bearer_response denial of service

> Remote attackers can cause a denial of service in Open5GS SGWC by manipulating modify bearer response messages, requiring a patch for mitigation.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 28 Jan 2026
- **Updated:** 23 Feb 2026
- **Also known as:** GHSA-4p7v-9jxw-m3mp

## What is CVE-2026-1522?

CVE-2026-1522 is a medium-severity denial of service vulnerability in Open5gs Open5gs, published on 28 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

A weakness has been identified in Open5GS up to 2.7.6. This vulnerability affects the function sgwc_s5c_handle_modify_bearer_response of the file src/sgwc/s5c-handler.c of the component SGWC. Executing a manipulation can lead to denial of service. The attack can be launched remotely. The exploit has been made available to the public and could be used for attacks. This patch is called b19cf6a. Applying a patch is advised to resolve this issue. The issue report is flagged as already-fixed.

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

## Which versions are affected by CVE-2026-1522?

It affects 1 product.


Products: Open5gs Open5gs.

## How do I fix CVE-2026-1522?

No fix has been published for CVE-2026-1522 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-1522 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-1522 exists.

## Other vulnerabilities in Open5gs Open5gs

- [CVE-2024-40130](https://insights.sbomify.com/CVE-2024-40130/): Memory corruption in n/a (critical 9.8)
- [CVE-2021-28122](https://insights.sbomify.com/CVE-2021-28122/): Missing authorization in n/a (critical 9.8)
- [CVE-2021-25863](https://insights.sbomify.com/CVE-2021-25863/): Hardcoded credentials in n/a (high 8.8)
- [CVE-2025-41067](https://insights.sbomify.com/CVE-2025-41067/): Reachable Assertion vulnerability in Open5GS (high 8.7)
- [CVE-2025-41068](https://insights.sbomify.com/CVE-2025-41068/): Reachable Assertion vulnerability in Open5GS (high 8.7)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-1522 and fix it if it is affected.

What it is: CVE-2026-1522 is a medium-severity denial of service vulnerability in Open5gs Open5gs, published on 28 Jan 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-1522 exists.

Affected product: Open5gs Open5gs. 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-2026-1522/ (Markdown: https://insights.sbomify.com/CVE-2026-1522/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-1522
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-1522
- OSV: https://osv.dev/vulnerability/CVE-2026-1522

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-1522/
Summaries are generated and may contain mistakes; the official description above is the record.