Vulnerability record · CVE-2026-45536 · published 12 June 2026
CVE-2026-45536: Netty information exposure vulnerability
Netty · Netty
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) — 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 → EAGAIN → Java maps to 0 → 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.
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) — 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 → EAGAIN → Java maps to 0 → 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.
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
| Link | Tags |
|---|---|
| https://github.com/netty/netty/releases/tag/netty-4.1.135.Final | Release Notes |
| https://github.com/netty/netty/releases/tag/netty-4.2.15.Final | Release Notes |
| https://github.com/netty/netty/security/advisories/GHSA-w573-9ffj-6ff9 | Vendor Advisory |
Track CVE-2026-45536 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2026-45536), CISA KEV, FIRST EPSS (scores of 2026-10-10). This page is refreshed as NVD updates the record.
