Look up another CVE · open CVE-2026-74527 in the interactive tracker
CVE-2026-74527
octeontx2-af: Block VFs from clobbering special CGX PKIND state
Published 2026-08-15 (2 months ago) by the Linux kernel CNA. Subsystem drivers/net. Debian urgency: not yet assigned.
What to do, per Debian release
Debian's own status for CVE-2026-74527 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 | vulnerable | 6.1.190-1 | No fix published anywhere yet, neither in Debian nor upstream for the series bookworm tracks. Watch the Debian tracker page for this CVE. Advisories for bookworm have historically landed a median of 23 days after publication. |
| Debian 13trixie | vulnerable | 6.12.113-1 | No fix published anywhere yet, neither in Debian nor upstream for the series trixie tracks. Watch the Debian tracker page for this CVE. Advisories for trixie have historically landed a median of 11 days after publication. |
| Debian 14forky | fixed | 7.1.8-1 | Update the kernel and reboot. Fixed in 7.1.8-1. A running kernel keeps the old code until the machine restarts. |
| Debian unstablesid | fixed | 7.1.8-1 | Update the kernel and reboot. Fixed in 7.1.8-1. A running kernel keeps the old code until the machine restarts. |
The vulnerability
What the bug is
PF and VF NIX LFs that share a CGX LMAC reuse the same hardware PKIND programming. When HiGig2 or EDSA parsing is enabled, a VF NIX LF alloc must not reset the LMAC RX PKIND or default TX parse config over the PF setup. Add cgx_get_pkind() and rvu_cgx_is_pkind_config_permitted() so VFs skip cgx_set_pkind(), rvu_npc_set_pkind(), and NIX_AF_LFX_TX_PARSE_CFG updates when the LMAC is using NPC_RX_HIGIG_PKIND or NPC_RX_EDSA_PKIND.
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/marvell/octeontx2/af/cgx.c
drivers/net/ethernet/marvell/octeontx2/af/cgx.h
drivers/net/ethernet/marvell/octeontx2/af/rvu.h
drivers/net/ethernet/marvell/octeontx2/af/rvu_cgx.c
drivers/net/ethernet/marvell/octeontx2/af/rvu_nix.c
drivers/net/ethernet/marvell/octeontx2/af/rvu_npc.c
- What this is
- MARVELL OCTEONTX2 RVU ADMIN FUNCTION DRIVERMAINTAINERS section matched on drivers/net/ethernet/marvell/octeontx2/af/ · netdev@vger.kernel.org · Maintained
- Kernel module
- rvu_af
Check it on the machine
grep -wE 'CONFIG_ETHERNET|CONFIG_NET_VENDOR_MARVELL|CONFIG_OCTEONTX2_AF|CONFIG_OCTEONTX2_MBOX' /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 rvu_afPrints 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 does not build this code in 1 release. It does build it in 3 releases, so the answer depends on which release the machine runs.
- bookwormn
- trixieMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt/amd64, arm64/cloud-arm64, armel/rpi, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x
- forky, sidMnot built on amd64/amd64, amd64/cloud-amd64, amd64/rt-amd64, arm64/cloud-arm64, armhf/armmp, armhf/armmp-lpae, loong64/loong64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x
- n
- not enabled on any flavour - this release does not build the code
- M
- a module where it is built at all; some flavours do not build it
- Build switches
- CONFIG_ETHERNET, CONFIG_NET_VENDOR_MARVELL, CONFIG_OCTEONTX2_AF, CONFIG_OCTEONTX2_MBOX
- 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
- 2026-08-15 (2 months ago)source
- CVSS
- 8.8 high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:Hsource recompute it - Attack vector
- local (AV:L)source
- EPSS
- 0.17%, higher than 6.3% of all CVEssource
- CISA KEV
- not listedthe KEV catalogue
- Debian urgency
- not yet assignedsource
- 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 |
|---|---|---|
| 4.20 | 6.18.57 | a76243488740 |
| 4.20 | 7.1.8 | d3c6b0f48f12 |
| 4.20 | 7.2 | 3bd438a58e91 |
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:LAttack vector, local
- Exploitation requires a malicious SR-IOV VF tenant to send NIX_LF_ALLOC mailbox messages over PCI BAR registers during netdev bring-up; the vulnerable AF code is not reachable from remote network packets.
- AC:LAttack complexity, low
- In the target OcteonTX2 DSA/HiGig multi-tenant deployment, a VF reliably triggers the bug by opening its netdev; no races or attacker-uncontrollable memory layout are needed once HiGig/EDSA parsing is enabled on the shared LMAC.
- PR:LPrivileges required, low
- The attacker is a cloud/NFV tenant with an assigned OcteonTX2 VF; triggering NIX LF allocation during interface up requires only guest-level netdev privileges (e.g., CAP_NET_ADMIN in the VM), not host root or init-namespace admin rights.
- UI:NUser interaction, none
- No victim interaction is required; the clobber occurs automatically when the attacker brings up or reinitializes their VF network interface through the standard driver probe/open path.
- S:CScope, changed
- A VF guest corrupts host-managed shared CGX LMAC hardware PKIND and NPC parse configuration, impacting the PF and other functions on that port beyond the VF's own security authority—crossing the VM/tenant isolation boundary.
- C:HConfidentiality impact, high
- Resetting HiGig/EDSA RX PKIND misconfigures NPC packet parsing for the entire shared LMAC, potentially misdelivering or exposing fabric/switch-tagged traffic intended for the PF or other tenants to the attacker's VF.
- I:HIntegrity impact, high
- The VF forcibly overwrites shared LMAC RX PKIND via cgx_set_pkind() and programs default TX parse config, corrupting host-controlled switching-header parsing that governs how transmitted and received fabric traffic is processed on the port.
- A:HAvailability impact, high
- Clobbering special HiGig/EDSA PKIND state breaks correct packet parsing for all PF/VF traffic on the shared LMAC, causing sustained loss of connectivity and denial of network service to the host and co-located tenants.