What is CVE-2026-80556?

CVE-2026-80556 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 2.6.27 onward and patched in 6.12.105, 6.18.46, 7.1.10 and others. CVE-2026-80556 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2026-80556?

CVE-2026-80556 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2026-80556?

Yes, CVE-2026-80556 has been patched. Fixed versions include 6.12.105, 6.18.46, 7.1.10 and others. If you are running Linux kernel 2.6.27 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2026-80556 actively exploited?

CVE-2026-80556 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2026-80556

High

In the Linux kernel, the following vulnerability has been resolved: mmc: atmel-mci: Fix use-after-free in atmci_remove due to race condition In atmci_probe, &host->bh_work is bound with atmci_work_func, and atmci_interrupt, atmci_timeout_timer and atmci_dma_complete can all queue this work on system_bh_wq. If we remove the module, atmci_remove makes cleanup and the memory allocated for host with devm_kzalloc() is released after the remove callback returns, while the work mentioned above may still be pending or running. The sequence of operations that may lead to a UAF bug is as follows: CPU0 CPU1 | atmci_interrupt | queue_work(system_bh_wq, | &host->bh_work) atmci_remove | atmci_cleanup_slot(...) | atmci_writel(host, ATMCI_IDR, ~0UL) | timer_delete_sync(&host->timer) | dma_release_channel(host->dma.chan) | free_irq(platform_get_irq(pdev, 0), host) | | atmci_work_func | // use host // devm resources released after | // remove returns, host is freed | | // use host (use-after-free) Fix it by canceling the work after all the sources that can schedule it (IRQ handler, timeout timer and DMA completion callback) have been stopped, and before proceeding with the remaining cleanup in atmci_remove.

Package Linux Kernel

Published 2026-08-26

Last modified 2026-08-27

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected versions

Linux kernel versions 2.6.27 and later are affected. Fixed in 6.12.105, 6.18.46, 7.1.10, 7.2 and their respective stable series.

Affected from

≥ 2.6.27

Fixed in

✓ 6.12.105 6.12.x ✓ 6.18.46 6.18.x ✓ 7.1.10 7.1.x ✓ 7.2

References

4 total

Details

CVE ID CVE-2026-80556

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2026-08-26

Modified 2026-08-27

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2026-80556?

CVE-2026-80556 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 2.6.27 onward and has been patched in 6.12.105, 6.18.46, 7.1.10 and others. CVE-2026-80556 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2026-80556?

CVE-2026-80556 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2026-80556?

Yes. CVE-2026-80556 has been patched. Fixed versions include 6.12.105, 6.18.46, 7.1.10 and others. If you are running Linux kernel 2.6.27 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2026-80556 actively exploited?

No. CVE-2026-80556 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.