CVE-2026-115863

Full vulnerability record from the local CVENow database.

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.

Severity

HIGH

CVSS score

7.6 (v3.1)

Vulnerability status

Awaiting Analysis

Source identifier

[email protected]

Published

2026-10-23 18:17:21.757000

Last modified

2026-10-23 19:43:46.190000

View original CVE JSON

{
  "id": "CVE-2026-115863",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-23T18:17:21.757",
  "lastModified": "2026-10-23T19:43:46.190",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "ConnMan",
          "product": "ConnMan",
          "defaultStatus": "unknown",
          "versions": [
            {
              "version": "0",
              "lessThanOrEqual": "2.0",
              "versionType": "custom",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H",
          "baseScore": 7.6,
          "baseSeverity": "HIGH",
          "attackVector": "ADJACENT_NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "LOW",
          "integrityImpact": "LOW",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 4.7
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Primary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-121"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://git.kernel.org/pub/scm/network/connman/connman.git/commit/?id=bb06c47101ca243fa5c04fb4b03fe2a12420d280",
      "source": "[email protected]"
    },
    {
      "url": "https://git.kernel.org/pub/scm/network/connman/connman.git/tree/gdhcp/client.c",
      "source": "[email protected]"
    },
    {
      "url": "https://lore.kernel.org/connman/[email protected]/",
      "source": "[email protected]"
    }
  ]
}