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Severity by source

Vendor (redhat) PRIMARY
5.3 MEDIUM
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
vuln.today AI
5.3 MEDIUM

Unauthenticated remote low-complexity attack over HTTP/2 (AV:N/AC:L/PR:N/UI:N); resource-exhaustion DoS affects only availability at limited level (A:L), no C/I impact, scope unchanged.

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

Primary rating from Vendor (redhat).

CVSS VectorVendor: redhat

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
Low

Lifecycle Timeline

3
Metadata Corrected
Sep 18, 2026 - 13:40 vuln.today
tag: Netty added
Analysis Generated
Sep 18, 2026 - 13:21 vuln.today
CVE Published
Sep 18, 2026 - 12:49 cve.org
MEDIUM 5.3

DescriptionCVE.org

A flaw was found in Netty's HTTP/2 HpackEncoder. A remote attacker can exploit this by sending HTTP/2 SETTINGS frames with a very large MAX_HEADER_TABLE_SIZE. This causes the HpackEncoder to store an excessive number of unique headers, leading to increased CPU usage and memory consumption, ultimately resulting in a Denial of Service (DoS).

AnalysisAI

Denial of service in Netty's HTTP/2 HPACK encoder (HpackEncoder) allows an unauthenticated remote attacker to force excessive CPU and memory consumption by sending SETTINGS frames that advertise an oversized MAX_HEADER_TABLE_SIZE, causing the encoder to retain an excessive number of unique header entries. The issue affects applications and Red Hat products that embed Netty and expose an HTTP/2 listener - including JBoss EAP 7 and 8, Keycloak, Red Hat Single Sign-On 7, AMQ Broker 7, Data Grid 8, Fuse 7, Quarkus, Camel 4 for Quarkus 3, Camel for Spring Boot 4, Apicurio Registry 3, and Debezium 3 - while HTTP/1.1-only endpoints are not exposed. …

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Attack ChainAIDerived

Hypothetical attack flow derived from CVE metadata

Access
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Delivery
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Exploit
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Execution
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Impact
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Vulnerability AssessmentAI

Exploitation Requires that the target application exposes an HTTP/2 listener backed by Netty's HpackEncoder and accepts attacker-supplied SETTINGS frames with a large MAX_HEADER_TABLE_SIZE (default HTTP/2 behavior). … Additional conditions and limiting factors are described in the full assessment.
Risk Assessment This is a genuine but low-to-moderate priority issue. … Full risk analysis with EPSS, KEV, and SSVC signal comparison available after sign-in.
Exploit Scenario Full exploit scenario with step-by-step reproduction available after sign-in.
Remediation No vendor-released patch has been identified at time of analysis, and the Red Hat references provided (https://access.redhat.com/security/cve/CVE-2026-93492 and https://bugzilla.redhat.com/show_bug.cgi?id=2536895) should be monitored for errata and for the specific fixed Netty build; upgrading to that release once published is the primary remediation, and rebuilding downstream products against the patched Netty is required since the flaw lives in a bundled library. … Detailed patch versions, workarounds, and compensating controls in full report.

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EUVD-2026-82903 vulnerability details – vuln.today

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