CVE-2026-93564 (CVSS 7.5)

Description

A flaw was found in Netty. A reference-count leak in the HAProxy PROXY-v2 message decoder allows a remote, unauthenticated attacker to send specially crafted PROXY-protocol v2 headers. This can lead to memory exhaustion, resulting in a Denial of Service (DoS) for the affected system.

Is your site exposed to CVE-2026-93564?

Run a free security scan — no signup, results in seconds.

CVSS v3.1 Score

7.5

HIGH

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

EPSS — Exploit Prediction

0.0056

Probability of exploitation

0.45%

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/errata/RHSA-2026:70257 https://access.redhat.com/security/cve/CVE-2026-93564 https://bugzilla.redhat.com/show_bug.cgi?id=2536953

Frequently Asked Questions

What is CVE-2026-93564? +

A flaw was found in Netty. A reference-count leak in the HAProxy PROXY-v2 message decoder allows a remote, unauthenticated attacker to send specially crafted PROXY-protocol v2 headers. This can lead to memory exhaustion, resulting in a Denial of Service (DoS) for the affected system. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-93564? +

CVE-2026-93564 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 0.0056, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-93564? +

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.

Related Vulnerabilities

CVE-2026-93558 7.5

A flaw was found in Netty's WebSocketServerExtensionHandler. A remote, unauthenticated attacker can exploit this vulnerability by using HTTP/1.1 pipelining to …

CVE-2026-93563 7.5

A flaw was found in Netty's `SmtpResponseDecoder` component. A remote attacker, acting as a malicious or man-in-the-middle (MITM) SMTP server, …

CVE-2026-93575 7.5

A flaw was found in Netty's MqttDecoder. An unauthenticated remote attacker can exploit this vulnerability by sending a specially crafted …

CVE-2026-93565 7.5

A flaw was found in Netty RtspDecoder. The `RtspMethods.valueOf()` function incorrectly strips trailing control bytes from method tokens in Real-Time …

CVE-2026-93494 7.5

A flaw was found in Netty's StompSubframeDecoder component. A remote attacker can exploit this vulnerability by sending a specially crafted …

CVE-2026-93560 7.5

A flaw was found in the Netty STOMP codec. A remote attacker could send a specially crafted STOMP frame with …

CVE-2026-93564