7.6
HIGH CVSS 3.1
CVE-2026-115863
ConnMan DHCPv6 Client Stack-Based Buffer Overflow
Description

ConnMan through 2.0 has a stack-based buffer overflow via a DHCPv6 Reply message. This occurs in get_domains in gdhcp/client.c. It copies a fixed NS_MAXDNAME (1025) bytes from a DHCPv6 DOMAIN_LIST (option 24) value into a 1026-byte stack buffer dns_name regardless of the actual option length, then walks DNS labels with an unbounded "c += jump + 1" loop. A crafted DHCPv6 REPLY with a DOMAIN_LIST option of >= 1025 non-zero bytes makes the label walk leave the buffer and read/write '.' past its end in attacker-chosen strides. An on-link attacker can trigger this without authentication via a forged Router Advertisement (O=1) and a forged DHCPv6 REPLY matching xid/CLIENTID with a long DOMAIN_LIST. The impact is unauthenticated on-link crash of connmand (runs as root). This was introduced in bb06c47.

INFO

Published Date :

Oct. 23, 2026, 6:17 p.m.

Last Modified :

Oct. 23, 2026, 7:43 p.m.

Remotely Exploit :

No
Affected Products

The following products are affected by CVE-2026-115863 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Connman connman
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 HIGH 8254265b-2729-46b6-b9e3-3dfca2d5bfca
CVSS 3.1 HIGH MITRE-CVE
CVSS 3.1 HIGH [email protected]
Solution
Update ConnMan to patch a stack-based buffer overflow vulnerability in DHCPv6 processing.
  • Update ConnMan to the latest version.
  • Apply vendor-provided patches for the vulnerability.
  • Ensure DHCPv6 client configurations are secure.
  • Monitor network for suspicious DHCPv6 traffic.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-115863.

URL Resource
https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=bb06c47101ca243fa5c04fb4b03fe2a12420d280
https://git.kernel.org/pub/scm/network/connman/connman.git/tree/gdhcp/client.c
https://lore.kernel.org/connman/[email protected]/
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-115863 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-115863 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-115863 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-115863 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Oct. 23, 2026

    Action Type Old Value New Value
    Added Description ConnMan through 2.0 has a stack-based buffer overflow via a DHCPv6 Reply message. This occurs in get_domains in gdhcp/client.c. It copies a fixed NS_MAXDNAME (1025) bytes from a DHCPv6 DOMAIN_LIST (option 24) value into a 1026-byte stack buffer dns_name regardless of the actual option length, then walks DNS labels with an unbounded "c += jump + 1" loop. A crafted DHCPv6 REPLY with a DOMAIN_LIST option of >= 1025 non-zero bytes makes the label walk leave the buffer and read/write '.' past its end in attacker-chosen strides. An on-link attacker can trigger this without authentication via a forged Router Advertisement (O=1) and a forged DHCPv6 REPLY matching xid/CLIENTID with a long DOMAIN_LIST. The impact is unauthenticated on-link crash of connmand (runs as root). This was introduced in bb06c47.
    Added CVSS V3.1 AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H
    Added CWE CWE-121
    Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/115xxx/CVE-2026-115863.json">CVE-2026-115863</a>
    Added Reference https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=bb06c47101ca243fa5c04fb4b03fe2a12420d280
    Added Reference https://git.kernel.org/pub/scm/network/connman/connman.git/tree/gdhcp/client.c
    Added Reference https://lore.kernel.org/connman/[email protected]/
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.