# CVE-2026-17100: Power System Out-of-bounds Write

> Authenticated attackers can execute arbitrary code in host firmware via a service processor mailbox interface vulnerability, gaining full system control.

- **Severity:** High 8.2 (`CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 19 Aug 2026
- **Updated:** 21 Aug 2026
- **Also known as:** GHSA-w82q-x75m-xp3p

## What is CVE-2026-17100?

CVE-2026-17100 is a high-severity memory corruption vulnerability in IBM Power Systems Firmware, published on 19 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

Power Systems Firmware FW1120.00, FW1110.00 through FW1110.30, FW1060.00 through FW1060.80, FW950.00 through FW950.H2, OP940.00 through OP940.a1, and OP940.00 - OP940.81 is affected by a vulnerability in the service processor mailbox interface. An attacker with authenticated service-level access to the BMC/FSP can exploit this vulnerability, allowing arbitrary code to be executed in the host firmware runtime, giving full control over the managed system, resulting in a confidentiality, integrity, and availability impact to the managed system.

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2026-17100?

It affects 29 products.


Products: Ibm Power Hardware Management Console \(7063-Cr2\) Firmware, Ibm Power System Ac922 \(8335-Gth\) Firmware, Ibm Power System Ac922 \(8335-Gtx\) Firmware, Ibm Power System E1050 \(9043-Mrx\) Firmware, Ibm Power System E1080 \(9080-Hex\) Firmware, Ibm Power System E1150 \(9043-Mru\) Firmware, Ibm Power System E1180 \(9080-Heu\) Firmware, Ibm Power System E950 \(9040-Mr9\) Firmware, Ibm Power System E980 \(9080-M9s\) Firmware, Ibm Power System H922 \(9223-22s\) Firmware, Ibm Power System H924 \(9223-42s\) Firmware, Ibm Power System L1022 \(9786-22h\) Firmware, Ibm Power System L1024 \(9786-42h\) Firmware, Ibm Power System L1122 \(9856-22h\) Firmware, Ibm Power System L1124 \(9856-42h\) Firmware, Ibm Power System S1012 \(9028-21b\) Firmware, Ibm Power System S1014 \(9105-41b\) Firmware, Ibm Power System S1022 \(9105-22a\) Firmware, Ibm Power System S1022s \(9105-22b\) Firmware, Ibm Power System S1024 \(9105-42a\) Firmware and 9 more.

## How do I fix CVE-2026-17100?

No fix has been published for CVE-2026-17100 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-17100 being exploited?

There is no known exploitation of CVE-2026-17100 in the wild and no public exploit code.

## Other vulnerabilities in IBM Power Systems Firmware

- [CVE-2026-16933](https://insights.sbomify.com/CVE-2026-16933/): Power System Integer Overflow (high 8.2)
- [CVE-2026-17093](https://insights.sbomify.com/CVE-2026-17093/): Power System Buffer Overflow (high 8.2)
- [CVE-2026-17429](https://insights.sbomify.com/CVE-2026-17429/): Power System Incorrect Authorization (high 8.1)
- [CVE-2026-17042](https://insights.sbomify.com/CVE-2026-17042/): Power System Out-of-bounds Read (high 7.3)
- [CVE-2021-38960](https://insights.sbomify.com/CVE-2021-38960/): Information disclosure in HMC (medium 5.3)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-17100 and fix it if it is affected.

What it is: CVE-2026-17100 is a high-severity memory corruption vulnerability in IBM Power Systems Firmware, published on 19 Aug 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-17100 in the wild and no public exploit code.

Affected product: IBM Power Systems Firmware. 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-2026-17100/ (Markdown: https://insights.sbomify.com/CVE-2026-17100/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-17100
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-17100
- OSV: https://osv.dev/vulnerability/CVE-2026-17100

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-17100/
Summaries are generated and may contain mistakes; the official description above is the record.