Look up another CVE · open CVE-2026-64035 in the interactive tracker
CVE-2026-64035
igc: set tx buffer type for SMD frames
Published 2026-07-19 (3 months ago) by the Linux kernel CNA. Subsystem drivers/net. Debian urgency: unimportant.
What to do, per Debian release
Debian's own status for CVE-2026-64035 in every release this site tracks, and what each one means in practice. Every status below is the one the Debian Security Team publishes for this CVE. source
| Release | Status | Version | What this means |
|---|---|---|---|
| Debian 12bookworm | not affected | 6.1.190-1 | Nothing to do. bookworm never shipped the vulnerable code. |
| Debian 13trixie | not affected | 6.12.113-1 | Nothing to do. trixie never shipped the vulnerable code. |
| Debian 14forky | fixed | 7.0.12-1 | Update the kernel and reboot. Fixed in 7.0.12-1. A running kernel keeps the old code until the machine restarts. |
| Debian unstablesid | fixed | 7.0.12-1 | Update the kernel and reboot. Fixed in 7.0.12-1. A running kernel keeps the old code until the machine restarts. |
The vulnerability
What the bug is
Sashiko pointed out that igc_fpe_init_smd_frame() initializes igc_tx_buffer fields for an SMD skb, but does not set the buffer type: https://sashiko.dev/#/patchset/20260415025226.114115-1-kohei%40enjuk.jp Since igc_tx_buffer entries are reused, a stale XDP or XSK type can remain and make TX completion use the wrong cleanup path. Set the buffer type to IGC_TX_BUFFER_TYPE_SKB.
Where it lives
The fix touches these files. If the subsystem is one you do not use, the practical exposure is lower, though the package is still the vulnerable one.
drivers/net/ethernet/intel/igc/igc_tsn.c
- What this is
- INTEL ETHERNET DRIVERSMAINTAINERS section matched on drivers/net/ethernet/intel/*/ · intel-wired-lan@lists.osuosl.org · Maintained
- Kernel module
- igc
Check it on the machine
grep -wE 'CONFIG_ETHERNET|CONFIG_IGC|CONFIG_NET_VENDOR_INTEL' /boot/config-$(uname -r)Reads the booted kernel's own configuration, on the machine and nowhere else. =y is built in, =m is a module, and an is not set line means the code is not there.
lsmod | grep -w igcPrints a line if that module is loaded right now, and nothing if it is not. One that is not loaded can still be loaded later by anything that needs it.
Show whether Debian builds this, per release
Debian builds this, but not on every flavour. At least one release below builds the code on some of its kernel flavours and not on others, so the answer depends on the architecture and flavour installed.
- bookwormMnot built on amd64/cloud-amd64, arm64/cloud-arm64
- trixieMnot built on amd64/cloud-amd64, arm64/cloud-arm64, armel/rpi
- forky, sidMnot built on amd64/cloud-amd64, arm64/cloud-arm64
- M
- a module where it is built at all; some flavours do not build it
- Build switches
- CONFIG_ETHERNET, CONFIG_IGC, CONFIG_NET_VENDOR_INTEL
- Reads as
- all on means the file is compiled; any one off means it is not.
From the configuration Debian publishes for every kernel flavour it builds. It covers only the architectures Debian ships a linux-config package for, and nothing about a kernel you built yourself. Debian's own status above stays authoritative about the source package.MAINTAINERS kbuild Makefiles Debian linux-config packages
Signals
- Published
- 2026-07-19 (3 months ago)source
- CVSS
- 9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsource recompute it - Attack vector
- network (AV:N)source
- EPSS
- 0.44%, higher than 37.0% of all CVEssource
- CISA KEV
- not listedthe KEV catalogue
- Debian urgency
- unimportantsource
- Subsystem
- drivers/net
Upstream fixes
The versions the CNA records as introducing and fixing this, and the commit for each. source
| Introduced | Fixed in | Commit |
|---|---|---|
| 6.16 | 6.18.34 | 1f83545f432d |
| 6.16 | 7.0.11 | 1c8587bd0252 |
| 6.16 | 7.1 | 5acc641e590e |
Why the CNA scored it this way
Quoted from the kernel CNA's own scoring file, word for word. A highlighted metric carries the most severe value CVSS v3.1 defines for it, which is what pushes the score up. source
- AV:NAttack vector, network
- The vulnerable TX completion path is reached when the igc driver receives an Ethernet SMD-V/SMD-R mPacket from a link partner and automatically transmits an SMD response frame; this is a network-delivered L2 frame processed in the RX/NAPI path per kernel network-reachability guidance.
- AC:LAttack complexity, low
- Once FPE/pMAC is enabled on the target, an attacker can repeatedly inject SMD-V frames to trigger SMD-R transmissions and race ring-slot reuse; stale XDP/XSK buffer types persist after prior transmissions on the same queue index, making reliable triggering feasible without conditions outside attacker influence.
- PR:NPrivileges required, none
- Exploitation requires only the ability to send Ethernet frames to a host that already has FPE/pMAC administratively enabled (expected in TSN/industrial deployments); the attacker does not need local accounts, CAP_NET_ADMIN, or any authenticated session to reach the vulnerable code path.
- UI:NUser interaction, none
- No victim interaction is required; SMD response transmission and the resulting erroneous TX cleanup occur automatically in interrupt/NAPI context in response to attacker-supplied link-layer frames.
- S:UScope, unchanged
- Impact is confined to kernel memory corruption and privilege escalation within the same kernel security domain; this is not a VM escape, IOMMU bypass, or cross-authority sandbox breakout.
- C:HConfidentiality impact, high
- Stale XDP buffer typing causes `xdp_return_frame()` to interpret an `sk_buff` pointer as an `xdp_frame`, a type confusion that reads attacker-influenced structure fields and can yield arbitrary kernel memory disclosure primitives.
- I:HIntegrity impact, high
- The wrong TX cleanup path performs improper `xdp_return_frame()`/`__xdp_return()` operations on mis-typed memory, enabling heap corruption and exploitable control-flow or arbitrary-write primitives typical of kernel type-confusion bugs.
- A:HAvailability impact, high
- Mis-typed TX buffer cleanup can immediately kernel-oops or panic via invalid page-pool returns, and repeated triggering leaks SKBs/DMA mappings causing sustained denial of service on the affected interface or host.