---
id: CVE-2026-56770
title: >-
  libais 0.15 - Out-of-bounds Vector Access in VdmStream::AddLine via Invalid
  Sequential Message ID
summary: >-
  libais through 0.15 VdmStream::AddLine uses an unchecked sentinel value as a
  vector index when processing AIS sentences with empty or out-of-range
  sequential message IDs. Remote attackers can crash services or vessel systems
  by sending c…
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cvssSource: cna
cwe:
  - CWE-129
vendor: schwehr
product: libais
affected:
  - libais <= 0.15
ssvc:
  exploitation: poc
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-06-25T18:28:27.282996Z'
exploitAvailable: true
published: '2026-06-25'
updated: '2026-11-08'
sourceUpdated: '2026-11-08T14:06:18.389Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-56770'
references:
  - url: 'https://github.com/schwehr/libais/issues/263'
    label: Researcher Disclosure
  - url: >-
      https://www.vulncheck.com/advisories/libais-out-of-bounds-vector-access-in-vdmstream-addline-via-invalid-sequential-message-id
tags:
  - cve.org
  - exploit-available
epss: 0.00582
epssPercentile: 0.48057
ingestedAt: '2026-11-08T14:51:22.344Z'
---

## Overview

libais through 0.15 VdmStream::AddLine uses an unchecked sentinel value as a vector index when processing AIS sentences with empty or out-of-range sequential message IDs. Remote attackers can crash services or vessel systems by sending crafted AIVDM sentences over VHF marine radio or IP feeds, causing out-of-bounds memory access and potential corruption.

## Affected

- `libais <= 0.15`

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.