Netty: Unix-socket fd receive leaks descriptors when peer sends two at once_CVE-2026-45536

{
    "lastseen": "",
    "description": "Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, netty_unix_socket_recvFd sets msg_control to `char control[CMSG_SPACE(sizeof(int))]` (line 940) \u2014 24 bytes on 64-bit Linux. A peer-sent SCM_RIGHTS cmsg carrying two ints has cmsg_len = CMSG_LEN(8) = 24, which fits exactly with no MSG_CTRUNC, so the kernel installs both fds in the receiving process. The subsequent check `cmsg->cmsg_len == CMSG_LEN(sizeof(int))` (line 972, expected 20) fails, the branch that would read the fd is skipped, and neither installed fd is closed. The for(;;) loop calls recvmsg again (non-blocking \u2192 EAGAIN \u2192 Java maps to 0 \u2192 read loop exits normally), leaving two leaked fds per message. There is no MSG_CTRUNC handling. Reachable via Epoll/KQueue DomainSocketChannel when the application opts into DomainSocketReadMode.FILE_DESCRIPTORS (non-default). Versions 4.1.135.Final and 4.2.15.Final patch the issue.",
    "published": "2026-06-12T14:12:48.126Z",
    "modified": "2026-06-12T15:05:36.411Z",
    "type": "cve",
    "title": "Netty: Unix-socket fd receive leaks descriptors when peer sends two at once",
    "source": "GitHub_M",
    "references": "https://github.com/netty/netty/security/advisories/GHSA-w573-9ffj-6ff9\nhttps://github.com/netty/netty/releases/tag/netty-4.1.135.Final\nhttps://github.com/netty/netty/releases/tag/netty-4.2.15.Final",
    "id": "CVE-2026-45536",
    "bulletinFamily": "",
    "cwe": [
        "CWE-200",
        "CWE-772"
    ],
    "cvelist": null,
    "sourceData": "netty netty >= 4.2.0.Final, < 4.2.15.Final\nnetty netty < 4.1.135.Final",
    "sourceHref": "",
    "cvss": {
        "score": 4,
        "severity": "MEDIUM",
        "vector": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "netty",
    "version": ">= 4.2.0.Final, < 4.2.15.Final",
    "vendor": "netty",
    "ai_description": "",
    "ai_severity": "",
    "ai_vendor": "",
    "ai_product": "",
    "ai_version": "",
    "ai_score": 0
}