CVE-2026-80821

Published Sep 4, 2026

Description

In the Linux kernel, the following vulnerability has been resolved: nvmet: pci-epf: put CQ ref on create_cq mapping failure nvmet_pci_epf_create_cq() calls nvmet_cq_create(), which takes a reference on the controller and installs the completion queue. If the subsequent PCI address-space mapping fails or returns a too-small partial mapping, the function jumps to err_internal / err_unmap_queue without calling nvmet_cq_put(). The matching put in nvmet_pci_epf_delete_cq() is gated on NVMET_PCI_EPF_Q_LIVE, which is only set after the mapping succeeds, so teardown never releases these references. A remote PCI host that drives Create IO CQ commands with a failing PRP1/pci_addr therefore leaks the CQ and a controller reference on each attempt. Drop the CQ reference on the mapping-failure paths. The err_internal and err_unmap_queue labels are only reachable after nvmet_cq_create() has succeeded, so this pairs the create/put correctly.

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EPSS — Exploit Prediction

0.0017
Probability of exploitation
0.06%
Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Frequently Asked Questions

What is CVE-2026-80821? +
In the Linux kernel, the following vulnerability has been resolved: nvmet: pci-epf: put CQ ref on create_cq mapping failure nvmet_pci_epf_create_cq() calls nvmet_cq_create(), which takes a reference on the controller and installs the completion queue. If the subsequent PCI address-space mapping fails or returns a too-small partial mapping, the function jumps to err_internal / err_unmap_queue without calling nvmet_cq_put(). The matching put in nvmet_pci_epf_delete_cq() is gated on NVMET_PCI_EPF_Q_LIVE, which is only set after the mapping succeeds, so teardown never releases these references. A remote PCI host that drives Create IO CQ commands with a failing PRP1/pci_addr therefore leaks the CQ and a controller reference on each attempt. Drop the CQ reference on the mapping-failure paths. The err_internal and err_unmap_queue labels are only reachable after nvmet_cq_create() has succeeded, so this pairs the create/put correctly.
How do I check if I'm vulnerable to CVE-2026-80821? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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