Linux KernelOperating system · Linux

CVE-2025-39956

MEDIUM · 5.5 CVSS v3.1 Published 2025-10-09
Fix available
A fix is available. Upgrade to 6.12.49 / 6.16.9 or later.
See remediation →
57/100
Remediation priority · Elevated
Zero-click Patch available

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
In the Linux kernel, the following vulnerability has been resolved: igc: don't fail igc_probe() on LED setup error When igc_led_setup() fails, igc_probe() fails and triggers kernel panic in free_netdev() since unregister_netdev() is not called. [1] This behavior can be tested using fault-injection framework, especially the failslab feature. [2] Since LED support is not mandatory, treat LED setup failures as non-fatal and continue probe with a warning message, consequently avoiding the kernel panic. [1] kernel BUG at net/core/dev.c:12047! Oops: invalid opcode: 0000 [#1] SMP NOPTI CPU: 0 UID: 0 PID: 937 Comm: repro-igc-led-e Not tainted 6.17.0-rc4-enjuk-tnguy-00865-gc4940196ab02 #64 PREEMPT(voluntary) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014 RIP: 0010:free_netdev+0x278/0x2b0 [...] Call Trace: <TASK> igc_probe+0x370/0x910 local_pci_probe+0x3a/0x80 pci_device_probe+0xd1/0x200 [...] [2] #!/bin/bash -ex FAILSLAB_PATH=/sys/kernel/debug/failslab/ DEVICE=0000:00:05.0 START_ADDR=$(grep " igc_led_setup" /proc/kallsyms \ | awk '{printf("0x%s", $1)}') END_ADDR=$(printf "0x%x" $((START_ADDR + 0x100))) echo $START_ADDR > $FAILSLAB_PATH/require-start echo $END_ADDR > $FAILSLAB_PATH/require-end echo 1 > $FAILSLAB_PATH/times echo 100 > $FAILSLAB_PATH/probability echo N > $FAILSLAB_PATH/ignore-gfp-wait echo $DEVICE > /sys/bus/pci/drivers/igc/bind

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis

A detailed technical summary for this CVE is being prepared.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Linux KernelOperating system
Affected:>= 6.9, < 6.12.49>= 6.13, < 6.16.9= 6.17

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 6.12.49 / 6.16.9 or later
Fixed in 6.12.496.16.9
Vendor patch git.kernel.org →
Recommended fix High confidence

6.12.49 (for 6.12.x) / 6.16.9 (for 6.16.x) / 6.17.x or later stable kernel

  1. Upgrade the Linux kernel to version 6.12.49 or later if running the 6.12.x stable branch
  2. Alternatively, upgrade to kernel version 6.16.9 or later if running the 6.16.x stable branch
  3. Alternatively, upgrade to kernel version 6.17.0 or later if running the 6.17.x stable branch
  4. Alternatively, upgrade to the latest stable kernel release (e.g., 6.17.x or newer) which contains this fix
  5. Reboot the system after kernel upgrade to apply the changes
Caveat Kernel upgrades typically require system reboot; minor driver behavior changes possible but unlikely to affect normal operation

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $1,600. Get the upgrade done

Scan for this in your stack

Free · runs locally
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-39956 in production — separate from our analysis above.

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