CVE-2026-45891

In the Linux kernel, the following vulnerability has been resolved: net: hns3: fix double free issue for tx spare buffer In hns3_set_ringparam(), a temporary copy (tmp_rings) of the ring structure is created for rollback. However, the tx_spare pointer in the original ring handle is incorrectly left pointing to the old backup memory. Later, if memory allocation fails in hns3_init_all_ring() during the setup, the error path attempts to free all newly allocated rings. Since tx_spare contains a stale (non-NULL) pointer from the backup, it is mistaken for a newly allocated buffer and is erroneously freed, leading to a double-free of the backup memory. The root cause is that the tx_spare field was not cleared after its value was saved in tmp_rings, leaving a dangling pointer. Fix this by setting tx_spare to NULL in the original ring structure when the creation of the new `tx_spare` fails. This ensures the error cleanup path only frees genuinely newly allocated buffers.

Package Linux Kernel
Published 2026-05-27
Last modified 2026-05-27
Patch available
Yes

Affected versions

Linux kernel versions 5.14 and later are affected. Fixed in 5.15.202, 6.1.165, 6.6.128, 6.12.75, 6.18.14, 6.19.4, 7.0 and their respective stable series.

Affected from
≥ 5.14
Fixed in
✓ 5.15.202 5.15.x ✓ 6.1.165 6.1.x ✓ 6.6.128 6.6.x ✓ 6.12.75 6.12.x ✓ 6.18.14 6.18.x ✓ 6.19.4 6.19.x ✓ 7.0

References

The following references provide additional information about CVE-2026-45891 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2026-45891?

    CVE-2026-45891 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 5.14 onward and has been patched in 5.15.202, 6.1.165, 6.6.128 and others. CVE-2026-45891 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • Is there a patch available for CVE-2026-45891?

    Yes — CVE-2026-45891 has been patched. Fixed versions include 5.15.202, 6.1.165, 6.6.128 and others. If you are running Linux kernel 5.14 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2026-45891 actively exploited?

    No — CVE-2026-45891 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.