CVE-2026-43156
CVE-2026-43156 is a medium-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 5.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low.
Key facts
- Severity: Medium (CVSS 3.x base score 5.5)
- EPSS exploit prediction: 0% (2nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-27715
- Affected product: Linux Linux Kernel
- Published:
- Last modified:
Description
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")
Frequently asked questions
- What is CVE-2026-43156?
- 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")
- How severe is CVE-2026-43156?
- CVE-2026-43156 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2026-43156 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2026-43156?
- CVE-2026-43156 primarily affects Linux Linux Kernel. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2026-43156?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-43156 have an EU (EUVD) identifier?
- Yes. CVE-2026-43156 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-27715.
- When was CVE-2026-43156 published?
- CVE-2026-43156 was published on 2026-05-06 and last updated on 2026-06-17.
References
- https://git.kernel.org/stable/c/229dc9b9db475ac900182bafe258943e0e054c6d
- https://git.kernel.org/stable/c/26b3ec62fa1a94ac801feca47f040fc729b3c174
- https://git.kernel.org/stable/c/2705709f6574a088aab246af72fc95f2fea51484
- https://git.kernel.org/stable/c/35854ed5c40b02f95824e44398f9d2ba33727203
- https://git.kernel.org/stable/c/3d7e6ce34f4fcc7083510c28b17a7c36462a25d4
- https://git.kernel.org/stable/c/67ba6b13dbcaf45681fb6758794c5ac5fa589a6c
- https://git.kernel.org/stable/c/a3e64e950a3981a8199de9798f6d21261b959171
- https://git.kernel.org/stable/c/d2e7c898cc02dfe42443489a67a45ed616cb76e9
Affected products (7)
- cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:2.6.12:-:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:2.6.12:rc2:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:2.6.12:rc3:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:2.6.12:rc4:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:2.6.12:rc5:*:*:*:*:*:*
- cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
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