Bug 2467206 (CVE-2026-43156)

Summary: CVE-2026-43156 kernel: net: usb: pegasus: enable basic endpoint checking
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
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Fixed In Version: Doc Type: ---
Doc Text:
A flaw was found in the Linux kernel's USB Pegasus driver. This vulnerability allows a local attacker to use a specially crafted USB device to bypass expected endpoint checks. By presenting unexpected transfer types, the malicious device could trigger a system assertion, potentially leading to a denial of service (DoS) condition.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-05-06 13:10:48 UTC
In the Linux kernel, the following vulnerability has been resolved:

net: usb: pegasus: enable basic endpoint checking

pegasus_probe() fills URBs with hardcoded endpoint pipes without
verifying the endpoint descriptors:

  - usb_rcvbulkpipe(dev, 1) for RX data
  - usb_sndbulkpipe(dev, 2) for TX data
  - usb_rcvintpipe(dev, 3)  for status interrupts

A malformed USB device can present these endpoints with transfer types
that differ from what the driver assumes.

Add a pegasus_usb_ep enum for endpoint numbers, replacing magic
constants throughout. Add usb_check_bulk_endpoints() and
usb_check_int_endpoints() calls before any resource allocation to
verify endpoint types before use, rejecting devices with mismatched
descriptors at probe time, and avoid triggering assertion.

Similar fix to
- commit 90b7f2961798 ("net: usb: rtl8150: enable basic endpoint checking")
- commit 9e7021d2aeae ("net: usb: catc: enable basic endpoint checking")