CVE-2026-89730

What the bug is

The trailing byte path in altera_cvp_send_block() dereferences a u32 pointer even when only 1-3 bytes remain in the input buffer. If the buffer ends at a page or scatterlist boundary, this can read past the valid image data and fault. Copy the remaining bytes into a zero-initialized u32 before writing the final word so only valid bytes are read from the input buffer.

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/fpga/altera-cvp.c

What this is

FPGA MANAGER FRAMEWORKMAINTAINERS section matched on drivers/fpga/ · linux-fpga@vger.kernel.org · Maintained

Kernel module

none to look for. The file would have gone into altera_cvp, and Debian does not compile it into that module, so finding altera_cvp in lsmod would say nothing about this CVE.

Check it on the machine

grep -wE 'CONFIG_FPGA|CONFIG_FPGA_MGR_ALTERA_CVP' /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.

Show whether Debian builds this, per release

Debian does not build this code. In 5 releases below, every kernel flavour Debian publishes has the switch off, so the vulnerable file is compiled into no kernel binary Debian ships.

• bookworm, trixie, forky, sid, bookworm · linux-6.12n

n

not enabled on any flavour - this release does not build the code

Build switches

CONFIG_FPGA, CONFIG_FPGA_MGR_ALTERA_CVP

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

2026-09-11 (37 days ago)source

CVSS

no vector published, unrated

Attack vector

not published

EPSS

0.22%, higher than 11.2% of all CVEssource

CISA KEV

not listedthe KEV catalogue

Debian urgency

not yet assignedsource

Subsystem

drivers/fpga

Upstream fixes

The versions the CNA records as introducing and fixing this, and the commit for each. source

Introduced	Fixed in	Commit
4.14	5.10.270	447b3c893987
4.14	5.15.221	3b8938f5fbcf
4.14	6.1.188	2564ac3d3b8b
4.14	6.6.157	8f3365ed2a5d
4.14	6.12.109	b138bc665e21
4.14	6.18.50	827ec385458a
4.14	7.2.4	4dc1051939e4
4.14	7.3	9da70a43b5fe

Debian advisories