HIGH

CVE-2026-54399

CVSS v3

7.5

HIGH

EPSS Score

0.9 %

exploit probability, as of 2026-10-17

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

org.apache.httpcomponents.core5:httpcore5Mavenfrom 5.5-alpha1 · fixed in 5.5-beta2

Vendor advisories

CVE-2026-54399 Red Hat Product Security55 products fixed · 37 known affected
org.apache.httpcomponents.core5/httpcore5: Apache HttpComponents Core: Denial of Service via excessive HTTP headers
httpcore as a component of Cryostat 4 · jenkins-2-plugins.src as a component of OpenShift Developer Tools and Services · jenkins.src as a component of OpenShift Developer Tools and Services
RHSA-2026:68333 Red Hat Product Security4 products fixed
Red Hat Security Advisory: Red Hat build of Cryostat security update
RHSA-2026:62260 Red Hat Product Security8 products fixed
Red Hat Security Advisory: Red Hat OpenShift Dev Spaces 3.30.0 Release.
RHSA-2026:61627 Red Hat Product Security2 products fixed
Red Hat Security Advisory: Red Hat AI Inference Server 3.2.2 (CUDA)
RHSA-2026:60259 Red Hat Product Security4 products fixed
Red Hat Security Advisory: Release of Red Hat OpenShift Developer Tools - Openshift Jenkins 4.20 security update.
RHSA-2026:60256 Red Hat Product Security4 products fixed
Red Hat Security Advisory: Release of Red Hat OpenShift Developer Tools - Openshift Jenkins 4.22 security update.

12 more advisories

Full record on NVD

Description

Uncontrolled Resource Consumption vulnerability in the HTTP/1.1 message parser in Apache HttpComponents Core (5.4.2 and earlier, 5.5-beta1 and earlier) allows an remote attacker to cause a denial of service through memory exhaustion by sending messages with excessive number of headers / excessive header length

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: 2026-07-01
Last Modified: 2026-07-01

Frequently asked questions

What is CVE-2026-54399?

Is CVE-2026-54399 actively exploited?

Active exploitation of CVE-2026-54399 has not been confirmed. Its EPSS score was 0.9% on 2026-10-17, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2026-54399?

CVE-2026-54399 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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