[CVE-2026-80717][MODERATE REGULAR] sctp: validate Adaptation Indication parameter length

[CVE-2026-80717][MODERATE REGULAR] sctp: validate Adaptation Indication parameter length

[AL-KERNEL]

CVE: CVE-2026-80717
Priority: MODERATE REGULAR
AL-KERNEL base severity: MODERATE
KPANIC flag: NO
Patch: sctp: validate Adaptation Indication parameter length
Commit: fa7861ddbe3b525b5d541c15c3953d3569e6eb0e
Upstream patch: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fa7861ddbe3b525b5d541c15c3953d3569e6eb0e
Original CVE announcement: https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80717
Analysis date: Fri, 28 Aug 2026 05:19:59 -0400
ActionableScore: 4
ActionableScore lower bound: 3
Actionable bucket: Borderline / manual review recommended
Manual review required: YES

Summary:
No one-sentence report phrase was found.

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

The original Linux kernel CVE announcement for CVE-2026-80717 is available here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80717

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 REGULAR
Manual review required: YES

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-2026-80717	MODERATE	CHECK WITH IMPACT FROM ORIG NN MODERATE	Maybe valid. Check manually. Hints by AL-KERNEL: The best (paranoid) CVSS is 'AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N';CWE-125;CWE-130;*CWE-200;BEST CVSS score: '5.3';DESCR 'An out-of-bounds read in SCTP parameter validation can occur because a header-only Adaptation Layer Indication parameter was accepted even though the parameter must contain a fixed 32 bit Adaptation Code Point. A remote peer can trigger this by sending a malformed INIT where the Adaptation Indication parameter declares only the generic parameter header and is placed at the end of the packet. In that case sctp_process_param can read four bytes beyond the declared parameter length at the receive skb tail, and the value may be copied into the state cookie returned in the INIT ACK. For the CVSS the PR:N is used because no local account or prior authentication is required beyond network reachability to the SCTP endpoint. Impact is limited confidentiality exposure of a few receive-buffer tail bytes. There is no evidence of an overwrite primitive, UAF, privilege escalation, or system-wide DoS from this patch context.';YES REQUIRES MANUAL CHECK; ,and ActionableScore result is Borderline / manual review recommended (with actual score 4)  SKIP CVE-2026-80717 UNKNOWN SKIP The Fixes patch not applied yet, so unlikely that actual: url YES  NO NO unknown 	MAYBE	INIT SIMPLEFIX NETWORK SKB LINUS  DECREASED_TO_MODERATEREG_BASED_ON_ACTIONABLESCORELESSTHAN5	-	-	checked

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

ActionableScore=4
ActionableScoreLower=3

1. ActionableScore
* Conservative score: 3
* Paranoid score: 4
* Final recommended bucket: **Borderline / manual review recommended**

2. Signal breakdown
* Remote reachable / network-triggerable: +2. A remote SCTP peer can send a malformed INIT with a header-only Adaptation Layer Indication parameter.
* Confidentiality impact plausible: +1. The bug may disclose four receive-buffer tail bytes via the INIT ACK state cookie.
* Common networking protocol receive path: +1 in the paranoid score only. SCTP is not as broadly exposed as TCP, but this is still unauthenticated network protocol parsing when an SCTP endpoint is reachable.
* Weak corruption / limited read-only OOB: +0. The primitive is a bounded out-of-bounds read, not an overwrite, UAF, double free, or type confusion.
* Availability impact: +0. The patch context describes disclosure, not crash or persistent DoS.
* Integrity impact: +0. No write or ownership-bypass primitive is shown.

3. Reachability analysis
The trigger is remote if an SCTP endpoint is reachable by the attacker. No local account or prior authentication is required, so PR:N is appropriate for CVSS. The malformed parameter is processed during INIT handling, before association establishment. SCTP is usually less exposed than TCP or UDP services and may depend on whether the protocol is enabled, loaded, and reachable through firewall policy. Containers and namespaces do not materially lower the required privilege because the main risk is from a remote peer to the SCTP listener.

4. Severity interpretation
This behaves like an actionable network-reachable Moderate issue, not an Important-class memory corruption bug. The realistic primitive is a small information disclosure of four bytes from the receive skb tail. There is no evidence in the patch of attacker-controlled memory corruption, privilege escalation, arbitrary read, arbitrary write, or kernel crash. The paranoid score is slightly higher only because unauthenticated network protocol parsing bugs deserve manual scrutiny even when the demonstrated leak is small.

5. One-sentence report phrase
A remote SCTP peer can send a malformed Adaptation Layer Indication parameter in an INIT packet, causing a limited out-of-bounds read that may disclose four receive-buffer tail bytes in the INIT ACK state cookie.

6. Manual review recommendation
MANUAL CHECK RECOMMENDED. This is network reachable and leaks kernel receive-buffer adjacent data, but the disclosed amount is small and the patch does not support memory corruption or privilege escalation.

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

Patch: sctp: validate Adaptation Indication parameter length
Commit: fa7861ddbe3b525b5d541c15c3953d3569e6eb0e
Upstream URL: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=fa7861ddbe3b525b5d541c15c3953d3569e6eb0e

Commit description:

The Adaptation Layer Indication parameter contains a fixed 32-bit
Adaptation Code Point after its parameter header. However,
sctp_verify_param() accepts a header-only parameter because the generic
parameter walker only requires the header to be present.

sctp_process_param() then reads adaptation_ind beyond the declared
parameter. When the malformed parameter is last in an INIT, the read
starts at the receive skb tail, and the value is copied into the state
cookie returned in the INIT ACK. This may disclose four receive-buffer
tail bytes.

Require the declared parameter length to match the fixed structure size
and abort the association through the existing invalid parameter length
path otherwise.

Fixes: 1da177e ("Linux-2.6.12-rc2")
Cc: stable@vger.kernel.org
Signed-off-by: Charles Vosburgh <trilobyte777@gmail.com>
Acked-by: Xin Long <lucien.xin@gmail.com>
Link: https://patch.msgid.link/20260727-sctp-adaptation-length-v1-1-0ab58b2810a5@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Changed files:
  net/sctp/sm_make_chunk.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=fa7861ddbe3b525b5d541c15c3953d3569e6eb0e

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

The original Linux kernel CVE announcement for CVE-2026-80717 can be found here:
https://lore.kernel.org/linux-cve-announce/?q=CVE-2026-80717

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: Not available
  The Best / paranoid CVSS vector: AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
  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: 3
  Paranoid ActionableScore: 4

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 REGULAR

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).