CVE-2023-53245

CVE-2023-53245 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. The underlying weakness is classified as CWE-476.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: scsi: storvsc: Fix handling of virtual Fibre Channel timeouts Hyper-V provides the ability to connect Fibre Channel LUNs to the host system and present them in a guest VM as a SCSI device. I/O to the vFC device is handled by the storvsc driver. The storvsc driver includes a partial integration with the FC transport implemented in the generic portion of the Linux SCSI subsystem so that FC attributes can be displayed in /sys. However, the partial integration means that some aspects of vFC don't work properly. Unfortunately, a full and correct integration isn't practical because of limitations in what Hyper-V provides to the guest. In particular, in the context of Hyper-V storvsc, the FC transport timeout function fc_eh_timed_out() causes a kernel panic because it can't find the rport and dereferences a NULL pointer. The original patch that added the call from storvsc_eh_timed_out() to fc_eh_timed_out() is faulty in this regard. In many cases a timeout is due to a transient condition, so the situation can be improved by just continuing to wait like with other I/O requests issued by storvsc, and avoiding the guaranteed panic. For a permanent failure, continuing to wait may result in a hung thread instead of a panic, which again may be better. So fix the panic by removing the storvsc call to fc_eh_timed_out(). This allows storvsc to keep waiting for a response. The change has been tested by users who experienced a panic in fc_eh_timed_out() due to transient timeouts, and it solves their problem. In the future we may want to deprecate the vFC functionality in storvsc since it can't be fully fixed. But it has current users for whom it is working well enough, so it should probably stay for a while longer.

Frequently asked questions

What is CVE-2023-53245?
In the Linux kernel, the following vulnerability has been resolved: scsi: storvsc: Fix handling of virtual Fibre Channel timeouts Hyper-V provides the ability to connect Fibre Channel LUNs to the host system and present them in a guest VM as a SCSI device. I/O to the vFC device is handled by the storvsc driver. The storvsc driver includes a partial integration with the FC transport implemented in the generic portion of the Linux SCSI subsystem so that FC attributes can be displayed in /sys. However, the partial integration means that some aspects of vFC don't work properly. Unfortunately, a full and correct integration isn't practical because of limitations in what Hyper-V provides to the guest. In particular, in the context of Hyper-V storvsc, the FC transport timeout function fc_eh_timed_out() causes a kernel panic because it can't find the rport and dereferences a NULL pointer. The original patch that added the call from storvsc_eh_timed_out() to fc_eh_timed_out() is faulty in this regard. In many cases a timeout is due to a transient condition, so the situation can be improved by just continuing to wait like with other I/O requests issued by storvsc, and avoiding the guaranteed panic. For a permanent failure, continuing to wait may result in a hung thread instead of a panic, which again may be better. So fix the panic by removing the storvsc call to fc_eh_timed_out(). This allows storvsc to keep waiting for a response. The change has been tested by users who experienced a panic in fc_eh_timed_out() due to transient timeouts, and it solves their problem. In the future we may want to deprecate the vFC functionality in storvsc since it can't be fully fixed. But it has current users for whom it is working well enough, so it should probably stay for a while longer.
How severe is CVE-2023-53245?
CVE-2023-53245 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-2023-53245 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (3rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-53245?
CVE-2023-53245 primarily affects Linux Linux Kernel. In total, 6 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-53245?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2023-53245 have an EU (EUVD) identifier?
Yes. CVE-2023-53245 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-59839.
When was CVE-2023-53245 published?
CVE-2023-53245 was published on 2025-09-15 and last updated on 2026-06-17.

References

Affected products (6)

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