---
id: CVE-2026-26456
title: >-
  A null pointer dereference vulnerability exists in the server-side session
  management logic of ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5
summary: >-
  A null pointer dereference vulnerability exists in the server-side session
  management logic of ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5. The issue
  is caused by a race condition between the request dispatch thread and the
  session cl…
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'
cwe:
  - CWE-362
  - CWE-476
published: '2026-08-27'
updated: '2026-09-08'
sourceUpdated: '2026-09-08T19:42:20.313'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-26456'
references:
  - url: 'https://github.com/ipflavors/ccoap'
    label: cve@mitre.org
  - url: >-
      https://github.com/songxpu/bug_report/blob/master/CoAP/ccoap/VULNERABILITY_REPORT5.md
    label: cve@mitre.org
tags:
  - nvd
epss: 0.00377
epssPercentile: 0.29017
ingestedAt: '2026-09-08T20:10:03.158Z'
---

## Overview

A null pointer dereference vulnerability exists in the server-side session management logic of ccoap 77f55c4b466e99327c24ace8a2913d3ba7e2ccd5. The issue is caused by a race condition between the request dispatch thread and the session cleanup thread when accessing shared session list nodes without proper synchronization.

## Remediation

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