---
id: CVE-2026-90782
title: >-
  S2OPC through 1.7.3 contains a null pointer dereference in
  msg_subscription_publish_bs__alloc_notification_message_items() where a failed
  allocation for DataChangeNotification is overwritten by a successful
  allocation for EventNotificati…
summary: >-
  S2OPC through 1.7.3 contains a null pointer dereference in
  msg_subscription_publish_bs__alloc_notification_message_items() where a failed
  allocation for DataChangeNotification is overwritten by a successful
  allocation for EventNotificati…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-476
vendor: Systerel
product: S2OPC
affected:
  - S2OPC <= 1.7.3
published: '2026-09-13'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T17:17:44.423'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-90782'
references:
  - url: 'https://gitlab.com/systerel/S2OPC'
    label: disclosure@vulncheck.com
  - url: >-
      https://gitlab.com/systerel/S2OPC/-/blob/S2OPC_Toolkit_1.7.3/src/ClientServer/services/b2c/msg_subscription_publish_bs.c#L106-L147
    label: disclosure@vulncheck.com
  - url: >-
      https://gitlab.com/systerel/S2OPC/-/commit/8848f051eed069b107ae7cb16a346d6f6386a8f5
    label: disclosure@vulncheck.com
  - url: 'https://gitlab.com/systerel/S2OPC/-/issues/1815'
    label: disclosure@vulncheck.com
  - url: 'https://gitlab.com/systerel/S2OPC/-/merge_requests/1862'
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/s2opc-through-1.7.3-null-pointer-dereference-in-alloc-notification-message-items
    label: disclosure@vulncheck.com
  - url: 'https://gitlab.com/systerel/S2OPC/-/issues/1815'
    label: 134c704f-9b21-4f2e-91b3-4a467353bcc0
tags:
  - nvd
  - exploit-available
  - cve.org
epss: 0.0032
epssPercentile: 0.25214
exploits:
  github: 1
  githubRepos:
    - 'https://github.com/HarshRajSinghania/CVE-2026-90782-s2opc-status-clobber'
  checkedAt: '2026-09-23T17:28:48.972Z'
exploitAvailable: true
ssvc:
  exploitation: poc
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-14T17:25:50.166515Z'
ingestedAt: '2026-09-14T15:23:07.470Z'
---

## Overview

S2OPC through 1.7.3 contains a null pointer dereference in msg_subscription_publish_bs__alloc_notification_message_items() where a failed allocation for DataChangeNotification is overwritten by a successful allocation for EventNotificationList. Attackers can trigger heap allocation failures on sessions with both data-change and event notifications to cause the server process to terminate.

## Remediation

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