CVE-2026-93566 (CVSS 6.5)

Description

A flaw was found in Netty. A remote attacker could exploit this by sending a specially crafted HTTP request that includes control characters within the chunk-size line. This bypasses the intended strict validation, allowing the attacker to inject arbitrary HTTP requests. This vulnerability can lead to HTTP request smuggling, potentially resulting in information disclosure or other unauthorized actions.

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CVSS v3.1 Score

6.5

MEDIUM

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

EPSS — Exploit Prediction

0.0048

Probability of exploitation

0.39%

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-1035 CWE-1035

References

Other References

https://access.redhat.com/errata/RHSA-2026:69440 https://access.redhat.com/errata/RHSA-2026:69470 https://access.redhat.com/security/cve/CVE-2026-93566 https://bugzilla.redhat.com/show_bug.cgi?id=2536954

Frequently Asked Questions

What is CVE-2026-93566? +

A flaw was found in Netty. A remote attacker could exploit this by sending a specially crafted HTTP request that includes control characters within the chunk-size line. This bypasses the intended strict validation, allowing the attacker to inject arbitrary HTTP requests. This vulnerability can lead to HTTP request smuggling, potentially resulting in information disclosure or other unauthorized actions. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-93566? +

CVE-2026-93566 has a CVSS v3.1 score of 6.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance. The EPSS score is 0.0048, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-93566? +

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-2026-93566