[CVE-2026-80832][MODERATE 7.0] crypto: qce - fix CCM AAD buffer underallocation

[CVE-2026-80832][MODERATE 7.0] crypto: qce - fix CCM AAD buffer underallocation

[AL-KERNEL]

CVE: CVE-2026-80832
Priority: MODERATE 7.0
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: crypto: qce - fix CCM AAD buffer underallocation
Commit: 11775b35ce9f27e73d62188d7d38aa0dc0a219aa
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=11775b35ce9f27e73d62188d7d38aa0dc0a219aa
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80832
Analysis date: Fri, 04 Sep 2026 14:16:14 -0400
ActionableScore: 5
ActionableScore lower bound: 4
Actionable bucket: Actionable Moderate at minimum
Manual review required: NO

Summary:
A buffer underallocation in the Qualcomm QCE CCM AAD path can cause the hardware engine to DMA read past the allocated buffer, producing incorrect authentication tags and creating a limited confidentiality and integrity concern on systems exposing the affected hardware crypto path.

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ABOUT THIS REPORT
======================================================================

The original Linux kernel CVE announcement for CVE-2026-80832 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80832

The original announcement does not normally provide a security severity
estimate, CVSS assessment, or enough information to determine whether the
reported kernel bug represents a practically relevant security issue.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin. It combines
an autonomous classifier with LLM-assisted technical analysis and a
separate ActionableScore mechanism.

The purpose of this report is to prioritize Linux kernel CVEs before
manual review, identify cases that require prompt investigation, and
support automatic closure of issues that are unlikely to have meaningful
security impact.

Published priority for this report: MODERATE 7.0
Manual review required: NO

A detailed explanation of the methodology and priority rules is included
at the end of this message.

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AL-KERNEL CLASSIFICATION RESULT
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CVE-2026-80832	MODERATE	https://www.kernelcve.org/list/?q=CVE-2026-80832 CHECK WITH IMPACT FROM ORIG NN LOW	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L';CWE-131;CWE-125;CWE-682;Other CVSS 'AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L';BEST CVSS score: '5.3';DESCR 'A buffer size calculation bug in the Qualcomm QCE CCM AAD path can allocate an AAD buffer smaller than the length later programmed into the DMA scatterlist. The hardware can then perform an out-of-bounds DMA read past the allocated buffer while computing the CBC-MAC over associated data. The directly observed impact is incorrect CCM authentication tags and crypto self-test failures, which can break AEAD operation and cause denial of service for users of the affected hardware crypto path. For the CVSS the PR:L is used because reliable triggering normally requires a local process or kernel consumer that can submit AEAD CCM requests through the crypto API or AF_ALG on a system with QCE hardware enabled. The issue is not directly network reachable by itself. Paranoid impact includes limited confidentiality concern because adjacent memory bytes may influence the generated authentication tag, but there is no clear write primitive or direct privilege escalation path from this patch alone.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Actionable Moderate at minimum (with actual score 5)	YES	DMAorINTERRUPT HARDWARE LINUS TEST  INCREASED_FROM_LOW_BASED_ON_REQUIREMANUALCHECK DECREASED_TO_MODERATEREG_BASED_ON_FALSEPOSCHECKOFKP	YES	NO	checked

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ACTIONABLESCORE ANALYSIS
======================================================================

ActionableScore=5
ActionableScoreLower=4

## 1. ActionableScore

* Conservative score: 4
* Paranoid score: 5
* Final recommended bucket: **Actionable Moderate at minimum**::

## 2. Signal breakdown

Triggered signals:

* Local unprivileged trigger: +1
  Likely possible if AEAD CCM through the crypto API is reachable from local users, for example via AF_ALG, on a system using the QCE driver.

* Memory layout invariant restoration: +1
  The patch fixes an inconsistency between allocated buffer size and DMA scatterlist length.

* Privileged kernel/device-management DMA-adjacent path: +1
  The bug is in a hardware crypto driver and causes the QCE engine to read past the allocated kernel buffer via DMA.

* Confidentiality impact plausible: +1
  Adjacent kernel memory bytes may be read by hardware and folded into the CCM authentication tag, but there is no direct memory disclosure primitive.

* Integrity impact plausible: +1
  The observed failure is incorrect CCM authentication tag generation, which can break cryptographic correctness.

* Availability impact realistic: +1
  The bug can cause CCM self-test failures and make the affected hardware AEAD path unreliable or unusable.

Subtractors:

* Rare hardware or configuration dependent: -1
  Requires Qualcomm QCE hardware and use of the affected AEAD CCM implementation.

* Corruption primitive constrained or no attacker-controlled target: -1
  This is an out-of-bounds DMA read, not an OOB write, UAF, arbitrary write, or controlled object corruption.

Conservative total: 4
Paranoid total: 5

## 3. Reachability analysis

The bug is not directly network reachable. A realistic trigger requires a local process or kernel consumer able to submit AEAD CCM requests to the affected QCE crypto implementation. AF_ALG may make this reachable to local unprivileged users depending on system configuration and algorithm exposure.

Namespaces do not inherently create or remove the bug, but container exposure depends on whether AF_ALG or crypto device access is available inside the container. The affected path is hardware specific and requires QCE support, so exposure is narrower than generic crypto API bugs.

## 4. Severity interpretation

This behaves like an Actionable Moderate issue rather than a clear Important issue. The patch shows a real allocation versus DMA length mismatch and an out-of-bounds DMA read, which is more security relevant than a pure correctness bug.

However, the demonstrated impact is incorrect authentication tags and crypto self-test failure. There is no supported write primitive, UAF reclaim, type confusion, arbitrary address access, or direct privilege escalation path. The paranoid score is raised because DMA reads of adjacent memory in a cryptographic path can have limited confidentiality and integrity implications, but the evidence does not justify treating it as strong memory corruption.

## 5. One-sentence report phrase

A buffer underallocation in the Qualcomm QCE CCM AAD path can cause the hardware engine to DMA read past the allocated buffer, producing incorrect authentication tags and creating a limited confidentiality and integrity concern on systems exposing the affected hardware crypto path.

## 6. Manual review recommendation

MANUAL CHECK RECOMMENDED

This should not be auto-closed because it involves DMA out-of-bounds read behavior in a cryptographic hardware driver. The practical impact appears limited, but the crypto and DMA context makes manual review appropriate.

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UPSTREAM PATCH SUMMARY
======================================================================

Patch: crypto: qce - fix CCM AAD buffer underallocation
Commit: 11775b35ce9f27e73d62188d7d38aa0dc0a219aa
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=11775b35ce9f27e73d62188d7d38aa0dc0a219aa

Commit description:

The AAD buffer allocated in qce_aead_ccm_prepare_buf_assoclen()
can be smaller than the length later programmed into the DMA
scatterlist.

The allocation size is currently calculated as:

  ALIGN(assoclen, 16) + MAX_CCM_ADATA_HEADER_LEN

while the DMA length is set to:

  ALIGN(assoclen + adata_header_len, 16)

Since ALIGN() does not distribute over addition, the allocation
can be smaller than the DMA length. For example, when
assoclen = 32 and adata_header_len = 2:

  allocation = ALIGN(32, 16) + 6 = 38
  DMA length = ALIGN(32 + 2, 16) = 48

As a result, the QCE hardware can read beyond the allocated
buffer while computing the CBC-MAC over the associated data.
The extra bytes are folded into the authentication tag,
resulting in an incorrect tag and causing CCM self-test
failures such as:

  alg: aead: ccm-aes-qce encryption test failed (wrong result)
  on test vector 8

Fix the allocation by adding the maximum possible AAD header
length before alignment:

  ALIGN(assoclen + MAX_CCM_ADATA_HEADER_LEN, 16)

This guarantees that the allocated buffer is large enough
for the fully padded AAD data for all supported header sizes.

Cc: stable@vger.kernel.org
Fixes: 9363efb ("crypto: qce - Add support for AEAD algorithms")
Signed-off-by: Md Sadre Alam <md.alam@oss.qualcomm.com>
Reviewed-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  drivers/crypto/qce/aead.c

Diff excerpt:

Not included in this email. See the upstream URL for the full patch.

Full patch:
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=11775b35ce9f27e73d62188d7d38aa0dc0a219aa

======================================================================
DETAILED REPORT METHODOLOGY
======================================================================

The original Linux kernel CVE announcement for CVE-2026-80832 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80832

The original CVE announcement normally does not include a security-level
estimate. In particular, it may not contain a CVSS assessment, an impact
level, or enough information to determine whether the reported bug is a
practically relevant security issue. One purpose of this parallel CVE list
is to provide that missing technical and prioritization information.

The original goal of the AL-KERNEL project was to prioritize Linux kernel
CVE analysis automatically before manual review. The system can also help
identify non-security issues that may be suitable for automatic closure.

This report was generated by AL-KERNEL, an AI-assisted Linux kernel
vulnerability analysis system developed by Alexander Larkin.

The first analysis stage combines an autonomous classifier with additional
LLM-based analysis. The autonomous classifier runs locally on a CPU and is
based on a backpropagation neural network. Together, these mechanisms
produce a technical vulnerability description, identify likely weakness
types, estimate CVSS severity, and provide input for ActionableScore.

Two CVSS estimates are retained because incomplete kernel vulnerability
information often permits more than one defensible interpretation:

  Conservative CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
  The Best / paranoid CVSS vector: AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
  The Best / paranoid CVSS score: 5.3

The conservative vector represents a lower-impact interpretation.
The Best/paranoid vector intentionally represents a plausible upper-bound
interpretation and should not automatically be treated as demonstrated
real-world impact.

CVSS may also need to be adjusted for a particular Linux deployment,
because actual reachability, privileges, enabled kernel configuration,
hardware, namespaces, exposed device nodes, and other environmental
conditions can differ significantly between systems.

A separate ActionableScore mechanism evaluates practical remediation
urgency. Its analysis may include reachability, attack prerequisites,
subsystem exposure, memory-corruption characteristics, denial-of-service
reliability, and possible confidentiality, integrity, or
privilege-escalation impact.

  Conservative ActionableScore: 4
  Paranoid ActionableScore: 5

The final base severity is taken directly from the second tab-separated
field of the AL-KERNEL classification result. ActionableScore does not
replace or independently override that final AL-KERNEL decision, and
if ActionableScore adjusted impact level of ALKERNEL, then you would see
self-readable flags above like INCREASED_TO_HIGH_BASED_ON_ACTIONABLESCOREHIGHEREQTHAN7.

For an AL-KERNEL result of MODERATE, this report uses the following
additional presentation split:

  ActionableScore below 5   -> MODERATE REGULAR
  ActionableScore 5 or more -> MODERATE 7.0

The distinction between MODERATE REGULAR and MODERATE 7.0 makes it
possible to identify Moderate issues that should receive manual analysis
and fixes before lower-priority MODERATE REGULAR issues. In many cases,
MODERATE REGULAR fixes may wait for a later rebase or routine update.

There is one override in which MODERATE REGULAR becomes MODERATE 7.0
even when the ActionableScore is below 5. When the AL-KERNEL result
contains the KPANIC flag, a MODERATE result is always presented as
MODERATE 7.0. The KPANIC flag selected with few regexps without
usage of AI at all, so it helps to detect cases when Kernel Crash happens
and similar (to filter False-Negative results from the LLM usage).

KPANIC indicates that a reliable kernel crash, kernel panic, or similarly
serious kernel availability impact was identified by the classification
workflow.

AL-KERNEL base severity for this report: MODERATE
KPANIC detected for this report: NO
Published priority for this report (same as in Subject): MODERATE 7.0

These results are intended to support engineering triage. They are
machine-generated estimates, and cases marked for manual review should
be validated by a human security engineer before final disposition.
For more info read docs linked from here: https://kernelcve.org/
(and you can submit you own patch there to generate such a report
for non-existant CVE-id yet).

Note that in many cases this AI tool selects higher severity, than
real is (means you can expect Importants instead of Moderate 7.0 or
Moderates 7.0 instead of regular Moderates). If you see such cases,
please use reply email interface to add additional manual analyses
info to this particular CVE.
And please, please, let me know when you see Lows instead of Importants
or Important instead of Low (because particular for such cases I
need to tune this AI tool to make it better for this one and next similar).
My contact email for such notifications is alexanjelausa@gmail.com (and both
send reply to CVE record itself too and see "reply" button below for howto reply).