CVE-2026-17042
HIGH 7.3IBM Power Systems Firmware FW950.00 through FW950.H2, OP940.00 through OP940.a1 (Power9), and OP940.00 - OP940.81 (Power HMC) is affected by a vulnerability in host firmware NVRAM parsing. An attacker with root access to a guest partition on an OpenPOWER system can write a specially crafted NVRAM image, causing the host firmware boot stage to crash with possible memory corruption. This condition persists until operator intervention — clearing NVRAM via the service processor — to restore normal operation. This vulnerability only affects OpenPOWER systems; systems running PowerVM are not affected. Successful exploitation results in an integrity and availability impact to the managed system.
Severe if exploited (CVSS 7.3), but no known exploitation and low modeled probability. Patch on a normal cadence.
Exploitation likelihood
0.1%chance of exploitation in 30 days · 1st percentile
Impact if exploited
7.3CVSS 3.1 · HIGH
- ConfidentialityNone
- IntegrityLow
- AvailabilityHigh
What an attacker needs
- ⚠Access: Requires local access to the host
- ⚠Privileges: Requires a low-privilege account
- ✓User interaction: No user interaction needed
- ✓Complexity: No special conditions — reliably repeatable
✓ lowers the bar for an attacker · ⚠ raises it
Proof of concept & exploit code
- github-search Search GitHub for public PoC repos
Test against your own equipment
curl -s https://vulnpedia.com/cve/CVE-2026-17042/poc.jsonMachine-readable PoC index for this CVE (for automation).Listed for defensive triage, patch verification, and authorized testing on systems you own. Machine-readable: /cve/CVE-2026-17042/poc.json
Weakness (CWE)
- CWE-125: Out-of-bounds Read
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H
All CVSS metrics
- HIGH 7.3 v3.1 · CNA Primary
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H - HIGH 7.3 v3.1 · NVD Primary
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:L/A:H