RHSA-2026:55861: Important: haproxy security update

Published Aug 17, 2026
·
Updated

Important: haproxy security update

Other sources

The haproxy packages provide a reliable, high-performance network load balancer for TCP and HTTP-based applications.Security Fix(es): haproxy: HAProxy: Denial of Service via HPACK dynamic table insertions (CVE-2026-55204) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section.

Red Hat

Affected Software

6 affected componentsFixes available
Red Hat Red Hat Enterprise Linux Server - AUS
Red Hat Red Hat Enterprise Linux for x86_64 - Extended Life Cycle Long Life
redhat/haproxy<1.8.27-2.el8_4.2
1.8.27-2.el8_4.2
redhat/haproxy<1.8.27-2.el8_4.2
1.8.27-2.el8_4.2
redhat/haproxy-debuginfo<1.8.27-2.el8_4.2
1.8.27-2.el8_4.2
redhat/haproxy-debugsource<1.8.27-2.el8_4.2
1.8.27-2.el8_4.2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/haproxy to a version that resolves this vulnerability.

    Fixed in 1.8.27-2.el8_4.2
  2. Upgrade

    Upgrade redhat/haproxy-debuginfo to a version that resolves this vulnerability.

    Fixed in 1.8.27-2.el8_4.2
  3. Upgrade

    Upgrade redhat/haproxy-debugsource to a version that resolves this vulnerability.

    Fixed in 1.8.27-2.el8_4.2

Event History

Aug 17, 2026
Advisory Published
via Red Hat·12:00 AM
Data Sourced
via Red Hat·12:00 AM
RemedyDescriptionAffected Software
Advisory Published
via Red Hat·07:44 PM
Data Sourced
via Red Hat·07:44 PM
Severity
Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of RHSA-2026:55861?

The severity of RHSA-2026:55861 is high with a score of 7.

2

What vulnerability is addressed in RHSA-2026:55861?

RHSA-2026:55861 addresses a Denial of Service vulnerability via HPACK dynamic table insertions, identified as CVE-2026-55204.

3

How do I fix RHSA-2026:55861?

To fix RHSA-2026:55861, you need to apply the updated haproxy packages provided in the security update.

4

What software is affected by RHSA-2026:55861?

The affected software includes haproxy packages on Red Hat Enterprise Linux Server and related distributions.

5

When was RHSA-2026:55861 published?

RHSA-2026:55861 was published on August 17, 2026.

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203