# CVE-2026-17136: IBM AIX and PowerVM VIOS format string vulnerability in NIM

Source: https://junglewise.ai/threats/cve-2026-17136-ibm-aix-and-powervm-vios-format-string-vulnerability-in-nim  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-20. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-17136 · Severity: critical · CVSS 9.8 · Published 2026-08-20

IBM AIX and PowerVM VIOS are core operating systems used to manage enterprise computing infrastructure and virtual machines. A format string vulnerability in the NIM (Network Installation Management) component could allow a remote attacker to execute arbitrary code with system-level privileges, potentially compromising the entire infrastructure and enabling unauthorized access to sensitive business operations.

Technologies: [IBM Aix](https://junglewise.ai/threats/technologies/aix), [IBM PowerVM VIOS](https://junglewise.ai/threats/technologies/powervm-vios). Vendors: [IBM](https://junglewise.ai/threats/vendors/ibm).

## Quick answers

**Is CVE-2026-17136 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-17136 being exploited in the wild.

**How severe is CVE-2026-17136?** Critical severity, with a CVSS score of 9.8, published 20 August 2026.

**Which products and versions are affected?** IBM Aix 7.2, 7.3; IBM PowerVM VIOS 4.1.

**Is there a fix for CVE-2026-17136?** 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-2026-17136 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-17136?** Check whether you run IBM Aix or IBM PowerVM VIOS 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 is a format string flaw in IBM AIX 7.2, 7.3, and PowerVM VIOS 4.1, likely within the NIM service used for remote system management and patching. Format string vulnerabilities occur when untrusted input is passed directly to a format function without proper validation, allowing attackers to read or write arbitrary memory. This vulnerability is network-accessible and requires no authentication or user interaction; an attacker can craft a malicious request to trigger code execution with the privileges of the NIM process. IBM has released security updates as part of Service Packs and Fix Packs to address this issue.

## Affected products

- IBM AIX 7.2, 7.3
- IBM PowerVM VIOS 4.1

## Timeline

- 2026-08-20: disclosed

## References

- [https://www.ibm.com/support/pages/node/7283858](https://www.ibm.com/support/pages/node/7283858)

## Related threats

- [IBM AIX format string vulnerability in privileged component](https://junglewise.ai/threats/cve-2026-16821-ibm-aix-format-string-vulnerability-in-privileged-component)
- [IBM AIX and PowerVM VIOS kernel memory corruption in directory reads](https://junglewise.ai/threats/cve-2026-19783-ibm-aix-and-powervm-vios-kernel-memory-corruption-in-directory)
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- [IBM AIX and PowerVM VIOS IPsec ESP stack memory corruption](https://junglewise.ai/threats/cve-2026-19448-ibm-aix-and-powervm-vios-ipsec-esp-stack-memory-corruption)
- [IBM AIX and PowerVM VIOS RPC DoS via malformed UDP packet](https://junglewise.ai/threats/cve-2026-19446-ibm-aix-and-powervm-vios-rpc-dos-via-malformed-udp-packet)