CVE-2026-93574: Request Smuggling (CVSS 6.5)

Description

A flaw was found in Netty's `netty-codec-http` component. A remote attacker could exploit this vulnerability by sending a specially crafted HTTP/1.1 chunk-size token that includes post-digit whitespace. This incorrect parsing of the chunk size can lead to HTTP request smuggling. This allows an attacker to bypass security controls or access unauthorized resources in proxy/backend deployments.

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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:N/I:L/A:L

EPSS — Exploit Prediction

0.0135

Probability of exploitation

0.71%

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-444 CWE-444

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-2026-93574 https://bugzilla.redhat.com/show_bug.cgi?id=2536966

Frequently Asked Questions

What is CVE-2026-93574? +

A flaw was found in Netty's `netty-codec-http` component. A remote attacker could exploit this vulnerability by sending a specially crafted HTTP/1.1 chunk-size token that includes post-digit whitespace. This incorrect parsing of the chunk size can lead to HTTP request smuggling. This allows an attacker to bypass security controls or access unauthorized resources in proxy/backend deployments. It has a CVSS v3.1 base score of 6.5 (MEDIUM).

How severe is CVE-2026-93574? +

CVE-2026-93574 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 0.0135, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-93574? +

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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