CVE-2026-74677
Description
A flaw was found in the Linux kernel's ipheth USB network driver. This vulnerability allows a local attacker with root privileges, using a specially crafted USB device, to trigger a Use-After-Free (UAF) condition. This occurs when the carrier_work mechanism attempts to access memory that has already been freed after the network interface has been closed or disconnected. Successful exploitation can lead to a system crash, resulting in a denial of service.
Statement
A use after free can occur in the ipheth USB network driver because carrier_work can be re armed by ipheth_sndbulk_callback after ipheth_close has already drained the delayed work. During disconnect, an in flight TX URB may complete with an error after unregister_netdev and ipheth_close, which can queue carrier_work again while the netdev private area that embeds the work item is later freed. A later timer or workqueue execution can dereference freed memory and crash the kernel. For the CVSS the PR:L is used for the paranoid score because a reduced local actor with delegated device or network control may be able to influence interface state and disconnect timing, even though the reported reproducer was driven as root. The issue is not network reachable in the normal IP packet sense and usually requires local USB device interaction or local control of the affected interface. Impact is at least local denial of service via kernel crash and in worst case may allow limited confidentiality or integrity impact due to the UAF class, so it should be reviewed manually.
Mitigation
Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 4.7 | N/A | N/A |
| Attack Vector | Local | N/A | N/A |
| Attack Complexity | High | N/A | N/A |
| Privileges Required | Low | N/A | N/A |
| User Interaction | None | N/A | N/A |
| Scope | Unchanged | N/A | N/A |
| Confidentiality | None | N/A | N/A |
| Integrity Impact | None | N/A | N/A |
| Availability Impact | High | N/A | N/A |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Integrity
Technical Impact: Modify Memory
The use of previously freed memory may corrupt valid data, if the memory area in question has been allocated and used properly elsewhere.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
If chunk consolidation occurs after the use of previously freed data, the process may crash when invalid data is used as chunk information.
Confidentiality
Technical Impact: Read Memory
Read operations on freed memory can sometimes leak sensitive information instead of causing a crash
Integrity,Confidentiality,Availability
Technical Impact: Execute Unauthorized Code or Commands
If malicious data is entered before chunk consolidation can take place, it may be possible to take advantage of a write-what-where primitive to execute arbitrary code. If the newly allocated data happens to hold a class, in C++ for example, various function pointers may be scattered within the heap data. If one of these function pointers is overwritten with an address to valid shellcode, execution of arbitrary code can be achieved.
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