IBM Power Systems Firmware: Stack-based buffer overflow in mailbox interface
Summary
IBM Power Systems Firmware FW1060.00 through FW1060.81 contains a stack-based buffer overflow in the service processor mailbox interface. An attacker with authenticated service-level access to the FSP can send a crafted mailbox message that overflows host firmware runtime attribute storage and executes arbitrary code in the host firmware runtime. Successful exploitation gives full access to the managed system's memory and hardware interfaces, with impact on confidentiality, integrity and availability.
Affected
- PowerVM Hypervisor / Power Systems Firmware FW1060.00 to FW1060.81
- Power 10 models listed in the IBM bulletin: S1022 (9105-22A), S1024 (9105-42A), S1022s (9105-22B), S1014 (9105-41B), L1022 (9786-22H), L1024 (9786-42H), E1050 (9043-MRX), S1012 (9028-21B)
- The bulletin text retrieved may be truncated; check the full model list in the advisory.
Fixed in
- Install FW1060.82 (1060_199) or newer
- Firmware is available via IBM Fix Central (per the IBM bulletin)
Workaround
Unknown. The IBM bulletin lists no workarounds or mitigations.
Exploitation
- Not known to be exploited in the wild; CISA SSVC lists exploitation as none and automatable as no.
- No public proof of concept found.
- The CVE is not in the CISA KEV catalogue.
- NVD was still awaiting analysis at the time of the data; the CVSS 8.2 score comes from IBM.
Our recommendation
- Check whether you operate any IBM Power systems; if not, no action is needed.
- Patch affected Power hosts to FW1060.82 or newer in the next maintenance window; check sibling IBM advisory CVE-2026-96262 in the same batch.
- Restrict FSP and HMC management interfaces to a segmented admin network and limit service-level credentials.
- Verify that no FSP or HMC management ports are reachable from the internet and monitor management-plane access.
Public exploits
PoC-in-GitHub, Metasploit and Exploit-DB list nothing for this CVE.
Research sources
- IBM Security Bulletin (node 7290126) www.ibm.com
- OpenCVE: CVE-2026-96264 app.opencve.io
- Positive Technologies PT-2026-110958 vulners.com
- TheHackerWire: CVE-2026-96264 www.thehackerwire.com
- IBM Security Bulletin (node 7290125, related CVE-2026-96262) www.ibm.com
Researched and written up in English and German by an AI (Claude by Anthropic) based on NVD, CISA, EPSS and the sources listed. The vendor information is authoritative. Researched on 1 Nov 2026, 16:34.
Original description (NVD)
IBM Power Systems Firmware FW1060.00 through FW1060.81 is affected by a vulnerability in the service processor mailbox interface. An attacker with authenticated service-level access to the FSP can send a specially crafted mailbox message to overflow host firmware runtime attribute storage, allowing arbitrary code to be executed in the host firmware runtime. This gives the attacker full access to the managed system's memory and hardware interfaces, resulting in a confidentiality, integrity, and availability impact to the managed system.
NVD references (1)
Sources
The tracker combines official, freely usable data sources – updated continuously:
- NVD (NIST) – CVEs, rating (CVSS), affected products
- CISA KEV – vulnerabilities confirmed by CISA as actively exploited
- CISA Vulnrichment – CISA assessment (SSVC) in the official CVE record
- FIRST EPSS – probability of exploitation
- Microsoft MSRC – Patch Tuesday: vulnerabilities, severity, updates
- PoC-in-GitHub – public proof-of-concept repositories
- Metasploit (Rapid7) – modules of the Metasploit Framework
- Exploit-DB (OffSec) – archive of public exploits (links only)
- Patch days: official vendor pages (linked per vendor) (Vendor patch days)
This product uses data from the NVD API but is not endorsed or certified by the NVD. EPSS data © FIRST.org.
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