Red Hat Security Advisory: haproxy security update
A denial of service vulnerability exists in HAProxy related to HPACK dynamic table insertions (CVE-2026-55204). This affects Red Hat Enterprise Linux 8 versions prior to 3.4.1 and related distributions. Red Hat has released security updates to address this issue. The vulnerability is rated with an important security impact by Red Hat Product Security.
AI Analysis
Technical Summary
The haproxy packages in Red Hat Enterprise Linux provide a high-performance network load balancer for TCP and HTTP applications. A denial of service vulnerability (CVE-2026-55204) exists due to improper handling of HPACK dynamic table insertions. Red Hat has issued security advisories and released updated packages to fix this vulnerability in affected versions of haproxy. The advisory covers multiple architectures and extended lifecycle versions of Red Hat Enterprise Linux 8. The vulnerability is tracked under Bugzilla ID 2490518.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to cause a denial of service condition in HAProxy, potentially disrupting network load balancing services. Red Hat rates the security impact as Important, indicating a high severity but not critical. There are no known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released updated haproxy packages that fix this vulnerability. Users should apply the security updates as described in the Red Hat advisories and the referenced article (https://access.redhat.com/articles/11258). Since a patch is available, remediation should be performed by updating to the fixed versions provided by Red Hat.
Red Hat Security Advisory: haproxy security update
Description
A denial of service vulnerability exists in HAProxy related to HPACK dynamic table insertions (CVE-2026-55204). This affects Red Hat Enterprise Linux 8 versions prior to 3.4.1 and related distributions. Red Hat has released security updates to address this issue. The vulnerability is rated with an important security impact by Red Hat Product Security.
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The haproxy packages in Red Hat Enterprise Linux provide a high-performance network load balancer for TCP and HTTP applications. A denial of service vulnerability (CVE-2026-55204) exists due to improper handling of HPACK dynamic table insertions. Red Hat has issued security advisories and released updated packages to fix this vulnerability in affected versions of haproxy. The advisory covers multiple architectures and extended lifecycle versions of Red Hat Enterprise Linux 8. The vulnerability is tracked under Bugzilla ID 2490518.
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to cause a denial of service condition in HAProxy, potentially disrupting network load balancing services. Red Hat rates the security impact as Important, indicating a high severity but not critical. There are no known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released updated haproxy packages that fix this vulnerability. Users should apply the security updates as described in the Red Hat advisories and the referenced article (https://access.redhat.com/articles/11258). Since a patch is available, remediation should be performed by updating to the fixed versions provided by Red Hat.
Technical Details
- Gcve Source
- db.gcve.eu
- Osv Id
- BIT-haproxy-2026-55204
- Osv Schema Version
- 1.6.2
- Aliases
- ["CVE-2026-55204"]
- Ecosystems
- ["Bitnami"]
- Database Specific Severity
- High
Threat ID: 6a42ed7327e9c79719939236
Added to database: 06/29/2026, 22:10:59 UTC
Last enriched: 09/10/2026, 22:45:33 UTC
Last updated: 09/20/2026, 10:01:33 UTC
Views: 92
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