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CVE-2026-53016
crypto: ccp - copy IV using skcipher ivsize
Published 2026-06-24 (4 months ago) by the Linux kernel CNA. Subsystem drivers/crypto. Debian urgency: not yet assigned.
What to do, per Debian release
Debian's own status for CVE-2026-53016 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 | fixedDLA-4665-1 · 2026-07-03 · text | 6.1.176-1 | Update the kernel and reboot. DLA-4665-1 shipped the fix on 2026-07-03, in 6.1.176-1. A running kernel keeps the old code until the machine restarts. |
| Debian 13trixie | fixed | 6.12.94-1 | Update the kernel and reboot. Fixed in 6.12.94-1. A running kernel keeps the old code until the machine restarts. |
| Debian 14forky | fixed | 7.0.10-1 | Update the kernel and reboot. Fixed in 7.0.10-1. A running kernel keeps the old code until the machine restarts. |
| Debian unstablesid | fixed | 7.0.10-1 | Update the kernel and reboot. Fixed in 7.0.10-1. A running kernel keeps the old code until the machine restarts. |
The vulnerability
What the bug is
AF_ALG rfc3686-ctr-aes-ccp requests pass an 8-byte IV to the driver. ccp_aes_complete() restores AES_BLOCK_SIZE bytes into the caller's IV buffer while RFC3686 skciphers expose an 8-byte IV, so the restore overruns the provided buffer. Use crypto_skcipher_ivsize() to copy only the algorithm's IV length.
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/crypto/ccp/ccp-crypto-aes.c
- What this is
- AMD CRYPTOGRAPHIC COPROCESSOR (CCP) DRIVERMAINTAINERS section matched on drivers/crypto/ccp/ · linux-crypto@vger.kernel.org · Supported
- Kernel module
- ccp_crypto
Check it on the machine
grep -wE 'CONFIG_CRYPTO|CONFIG_CRYPTO_DEV_CCP|CONFIG_CRYPTO_DEV_CCP_CRYPTO' /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 ccp_cryptoPrints 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/arm64, arm64/cloud-arm64, arm64/rt/arm64, armhf/armmp, armhf/armmp-lpae, armhf/rt/armmp, ppc64el/powerpc64le
- trixieMnot built on amd64/cloud-amd64, arm64/arm64, arm64/arm64-16k, arm64/cloud-arm64, arm64/rt/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/cloud-amd64, arm64/arm64, arm64/arm64-16k, arm64/cloud-arm64, arm64/rt-arm64, armhf/armmp, armhf/armmp-lpae, loong64/loong64, ppc64el/powerpc64le, ppc64el/powerpc64le-64k, riscv64/riscv64, s390x/s390x
- M
- a module where it is built at all; some flavours do not build it
- Build switches
- CONFIG_CRYPTO, CONFIG_CRYPTO_DEV_CCP, CONFIG_CRYPTO_DEV_CCP_CRYPTO
- 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
- 2026-06-24 (4 months ago)source
- CVSS
- 7.8 high
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsource recompute it - Attack vector
- local (AV:L)source
- EPSS
- 0.14%, higher than 3.0% of all CVEssource
- CISA KEV
- not listedthe KEV catalogue
- Debian urgency
- not yet assignedsource
- Subsystem
- drivers/crypto
Upstream fixes
The versions the CNA records as introducing and fixing this, and the commit for each. source
| Introduced | Fixed in | Commit |
|---|---|---|
| 3.14 | 5.10.258 | 939061b2d0f7 |
| 3.14 | 5.15.209 | 798d409a8949 |
| 3.14 | 6.1.175 | dfb2cf434829 |
| 3.14 | 6.6.141 | eecee15e263c |
| 3.14 | 6.12.91 | bb01d8f1f385 |
| 3.14 | 6.18.33 | df9784bb5b63 |
| 3.14 | 7.0.10 | 227c1e1d9e2a |
| 3.14 | 7.1 | a7a1f3cdd64d |
Debian advisories
| Advisory | Date | Shipped to | Debian |
|---|---|---|---|
| DLA-4671-1 | 2026-07-05 | bullseye 6.1.176-1~deb11u1 | tracker |
| DLA-4665-1 | 2026-07-03 | bookworm 6.1.176-1 | tracker |
| DLA-4664-1 | 2026-07-03 | bullseye 5.10.259-1 | tracker |
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
- The vulnerable CCP skcipher path is reached through local AF_ALG socket syscalls, not by processing remote packets. An attacker binds an AF_ALG skcipher socket to `rfc3686-ctr-aes-ccp` and submits a request locally.
- AC:LAttack complexity, low
- Once the affected CCP algorithm is present, the trigger is a deterministic AF_ALG request with an 8-byte RFC3686 IV. No race or condition outside the attacker's control is required.
- PR:LPrivileges required, low
- AF_ALG socket creation, bind, key setup, accept, sendmsg, and recvmsg have no capability checks, so a basic unprivileged local user can reach the bug. The driver-only flag can be selected through the allowed AF_ALG feature/mask fields.
- UI:NUser interaction, none
- Exploitation is entirely driven by the attacker's local syscalls. No separate victim action is required.
- S:UScope, unchanged
- The vulnerability corrupts kernel memory within the same kernel security authority. It does not cross a VM, IOMMU, or similar security boundary.
- C:HConfidentiality impact, high
- The bug is an attacker-reachable kernel heap out-of-bounds write caused by copying 16 IV bytes into an 8-byte AF_ALG IV buffer. Kernel memory corruption can reasonably be developed into information disclosure primitives.
- I:HIntegrity impact, high
- The overwrite corrupts adjacent kernel heap memory from an unprivileged request path. As an out-of-bounds write, it is defensibly scored as potentially enabling arbitrary memory modification or control-flow compromise.
- A:HAvailability impact, high
- Even without full exploitation, the heap corruption can crash or destabilize the kernel. Repeated unprivileged triggering can therefore cause high availability impact.