Is CVE-2026-17503 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-17503 being exploited in the wild.

How severe is CVE-2026-17503?

Medium severity, with a CVSS score of 5.1, published 24 September 2026.

Which products and versions are affected?

IBM PowerVM Hypervisor FW1120.00-FW1120.01, FW1110.00-FW1110.31, FW1060.00-FW1060.81, FW950.00-FW950.H3.

Is there a fix for CVE-2026-17503?

No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.

How is CVE-2026-17503 attacked?

It is attacked with local access, in device firmware.

Am I affected by CVE-2026-17503?

Check whether you run IBM PowerVM Hypervisor at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-17503: IBM PowerVM Hypervisor partition firmware boot configuration integrity bypass

CVE-2026-17503 · Severity: medium · CVSS 5.1 · Published 2026-09-24

IBM PowerVM Hypervisor, which manages virtual partitions on Power Systems servers, contains a vulnerability in how it validates partition boot configuration data. An attacker with administrator access to a virtual partition can corrupt the partition's firmware settings to prevent it from booting, causing an outage that requires manual intervention by a system operator to fix. This impacts the availability of virtualized workloads running on affected Power Systems.

Technologies: IBM PowerVM Hypervisor. Vendors: IBM.

Quick answers

Is CVE-2026-17503 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-17503 being exploited in the wild.
How severe is CVE-2026-17503?: Medium severity, with a CVSS score of 5.1, published 24 September 2026.
Which products and versions are affected?: IBM PowerVM Hypervisor FW1120.00-FW1120.01, FW1110.00-FW1110.31, FW1060.00-FW1060.81, FW950.00-FW950.H3.
Is there a fix for CVE-2026-17503?: No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-17503 attacked?: It is attacked with local access, in device firmware.
Am I affected by CVE-2026-17503?: Check whether you run IBM PowerVM Hypervisor at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

The vulnerability exists in the partition firmware runtime boot configuration validation, where improper input validation (CWE-20) allows an attacker with root/high privileges on a partition to maliciously modify partition NVRAM settings. Exploitation requires local access with high privileges to the partition; successful exploitation results in denial of service and integrity impact. Patches are available for all affected firmware versions (FW950.H4+, FW1060.82+, FW1110.32+, FW1120.02+).

Affected products

IBM PowerVM Hypervisor FW1120.00-FW1120.01, FW1110.00-FW1110.31, FW1060.00-FW1060.81, FW950.00-FW950.H3

Timeline

2026-09-24: disclosed: IBM Security Bulletin published

References

https://www.ibm.com/support/pages/node/7289133

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