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TI-2026-85709 Aliases CVE-2026-85068

Uninitialized stack memory leak in NUT blazer_usb driver

Priority LOW 11CWE-457Published · Updated

Key facts

Attack vector
Physical
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-457 and the CVSS impact.

Summary

Network UPS Tools (nut) from 2.4.2 through 2.8.5 is affected. The blazer_usb driver partly initializes a 64-byte buffer in ippon_command (CWE-457), so uninitialized stack bytes are sent to the USB device. A malicious firmware-controlled USB device can receive these bytes during normal polling if an attacker has physical or supply-chain access to the USB bus. The leak is read-only and has no established integrity or availability impact.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

Description from the CNA

Network UPS Tools is a collection of programs which provide a common interface for monitoring and administering UPS, PDU and SCD hardware. From 2.4.2 through 2.8.5, ippon_command in drivers/blazer_usb.c partially initializes char tmp[64] with a short Megatec status query and then passes a fixed eight-byte chunk to usb_control_msg. A malicious firmware-controlled USB device presenting the Mustek Powermust VID 0x06da and Mustek Powermust PID 0x0003 matches blazer_usb_id, selects ippon_subdriver, and can receive the uninitialized trailing stack bytes during normal polling. The disclosure is bounded and read-only, requires physical or supply-chain access to the USB bus, and has no established integrity or availability impact. This issue is scheduled to be fixed in version 2.8.6.

Why it matters now

EPSS 0.00151 4th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
networkupstoolsnut2.4.2 – 2.8.5—No fix listedCNA
  • nut Vendornetworkupstools Affected 2.4.2 – 2.8.5 Fixed in — No fix listed CNA

Remediation

The sources list no fixed version for nut. The source description says the fix is scheduled for version 2.8.6.

Written with Claude Haiku 5.5 from the sources below · 2026-11-07

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-11-05 Threatist record created from CVE-2026-85068
  2. 2026-11-07 Affected versions changed · Red Hat
  3. 2026-11-07 CVSS score added · Red Hat

References

Other 3

  • TI-2012-02556 Buffer overflow in the addchar function in common/parseconf.c in upsd in Network UPS… CVSS 2.0HIGH 7.5
  • TI-2026-84486 Command injection in Network UPS Tools upsmon via ups.alarm CVSS 3.1HIGH 8.1
  • TI-2026-39070 Network UPS Tools: A PWN Request in make-dist workflow can execute PR-controlled code with write-scoped GITHUB_TOKEN CVSS 3.1HIGH 8.2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences