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.
History

Mon, 02 Nov 2026 17:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Fri, 23 Oct 2026 23:00:00 +0000

Type Values Removed Values Added
First Time appeared Connman
Connman connman
Vendors & Products Connman
Connman connman

Fri, 23 Oct 2026 20:15:00 +0000

Type Values Removed Values Added
Title Stack-Based Buffer Overflow in ConnMan DHCPv6 Processing Allows Crash

Fri, 23 Oct 2026 18:45:00 +0000

Type Values Removed Values Added
Title Stack-Based Buffer Overflow in ConnMan DHCPv6 Processing Allows Crash

Fri, 23 Oct 2026 17:45:00 +0000

Type Values Removed Values 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.
Weaknesses CWE-121
References
Metrics cvssV3_1

{'score': 7.6, 'vector': 'CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2026-10-23T17:35:18.517Z

Updated: 2026-11-02T16:52:00.300Z

Reserved: 2026-10-23T17:35:18.141Z

Link: CVE-2026-115863

cve-icon Vulnrichment

Updated: 2026-11-02T16:51:55.463Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-10-23T18:17:21.757

Modified: 2026-11-02T17:17:36.563

Link: CVE-2026-115863

cve-icon Redhat

No data.