CVE-2026-62380: netty — Fix

Description

Netty (io.netty:netty-codec-socks) versions 4.2.0.Final through 4.2.16.Final and 4.1.x through 4.1.136.Final contain null byte, CRLF, and credential injection vulnerabilities in the SOCKS4 (Socks4ClientEncoder) and SOCKS5 (Socks5ClientEncoder) client encoders, which fail to validate domain address and authentication (username/password) fields. An attacker able to control these fields can inject null bytes or CRLF characters to truncate or alter values, potentially enabling domain spoofing, SOCKS4 userid truncation, authentication data injection, and protocol confusion. Fixed in 4.2.17.Final and 4.1.137.Final.

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CVSS v3.1 Score

7.5

HIGH

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

EPSS — Exploit Prediction

0.0025

Probability of exploitation

0.17%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-626 CWE-626

Affected Products

Vendor	Product	Versions
netty	netty	< 4.1.137
netty	netty	4.2.0 — 4.2.17

References

Advisories & Patches

https://github.com/netty/netty/security/advisories/GHSA-cc6x-ffm5-83wf

Other References

https://www.vulncheck.com/advisories/netty-before-final-socks-proxy-null-byte-injection

Frequently Asked Questions

What is CVE-2026-62380? +

Netty (io.netty:netty-codec-socks) versions 4.2.0.Final through 4.2.16.Final and 4.1.x through 4.1.136.Final contain null byte, CRLF, and credential injection vulnerabilities in the SOCKS4 (Socks4ClientEncoder) and SOCKS5 (Socks5ClientEncoder) client encoders, which fail to validate domain address and authentication (username/password) fields. An attacker able to control these fields can inject null bytes or CRLF characters to truncate or alter values, potentially enabling domain spoofing, SOCKS4 userid truncation, authentication data injection, and protocol confusion. Fixed in 4.2.17.Final and 4.1.137.Final. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-62380? +

CVE-2026-62380 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0025, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-62380? +

CVE-2026-62380 affects products from netty, specifically: netty. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-62380? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2026-62380