How severe is GHSA-w573-9ffj-6ff9?

GHSA-w573-9ffj-6ff9 has a CVSS score of 4/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by GHSA-w573-9ffj-6ff9?

GHSA-w573-9ffj-6ff9 affects the following packages: io.netty:netty-transport-native-epoll (Maven), io.netty:netty-transport-native-kqueue (Maven), io.netty:netty-transport-native-kqueue (Maven), io.netty:netty-transport-native-epoll (Maven). Ecosystems affected: Maven.

How do I fix GHSA-w573-9ffj-6ff9?

Update io.netty:netty-transport-native-epoll to 4.2.15.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w573-9ffj-6ff9 is resolved across your whole dependency graph.

How do I detect GHSA-w573-9ffj-6ff9 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.netty:netty-transport-native-epoll. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-w573-9ffj-6ff9 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-w573-9ffj-6ff9?

O3 pinpoints whether GHSA-w573-9ffj-6ff9 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-w573-9ffj-6ff9 actively exploited in the wild?

No public exploit code has been indexed for GHSA-w573-9ffj-6ff9 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for GHSA-w573-9ffj-6ff9?

GHSA-w573-9ffj-6ff9 has an EPSS (Exploit Prediction Scoring System) score of 0.1%, placing it in the 3th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is GHSA-w573-9ffj-6ff9?

GHSA-w573-9ffj-6ff9 is classified as Information Exposure (CWE-200), CWE-772 (CWE-772). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation.

When was GHSA-w573-9ffj-6ff9 published, and has it been updated?

GHSA-w573-9ffj-6ff9 was published on June 8, 2026 and was last updated on June 12, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕ Maven

GHSA-w573-9ffj-6ff9

MEDIUM

Netty: Unix-socket fd receive leaks descriptors when peer sends two at once

Also known asCVE-2026-45536

Published

Jun 8, 2026

Updated

Jun 12, 2026

Affected

4 pkgs

Patched

4 / 4

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.1%probability of exploitation in next 30 days

Lower Risk3th percentile0.00%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

4 pkgs affected

☕io.netty:netty-transport-native-epoll☕io.netty:netty-transport-native-kqueue☕io.netty:netty-transport-native-kqueue☕io.netty:netty-transport-native-epoll

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

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).

Affected Packages

4 total 4 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`io.netty:netty-transport-native-epoll`	≥ 4.2.0.Final&&< 4.2.15.Final	4.2.15.Final
☕Maven	`io.netty:netty-transport-native-kqueue`	≥ 4.2.0.Final&&< 4.2.15.Final	4.2.15.Final
☕Maven	`io.netty:netty-transport-native-kqueue`	all versions	4.1.135.Final
☕Maven	`io.netty:netty-transport-native-epoll`	all versions	4.1.135.Final

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.netty:netty-transport-native-epoll. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update io.netty:netty-transport-native-epoll to 4.2.15.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-w573-9ffj-6ff9 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-w573-9ffj-6ff9 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-w573-9ffj-6ff9. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

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

O3 Security · Impact-Aware SCA

Is GHSA-w573-9ffj-6ff9 in your dependencies?

O3 detects GHSA-w573-9ffj-6ff9 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works