Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
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.
Primary rating from Vendor (redhat).
CVSS VectorVendor: redhat
Lifecycle Timeline
3DescriptionCVE.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. …
Unlock full vulnerability intelligence
- Risk assessment & exploitation conditions
- Attack chain visualization
- Remediation with exact patch versions
- Threat intelligence from 22 sources
- Personal watchlist & email alerts
Free forever · No credit card required
Attack ChainAIDerived
Hypothetical attack flow derived from CVE metadata
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. |
Threat intelligence, references, and detailed analysis are available after sign-in.
More in Red Hat Build Of Keycloak
View allAccount takeover in Red Hat Build of Keycloak allows an unauthenticated attacker to abuse the reset-credentials flow in
Account takeover in Keycloak (Red Hat build of Keycloak, Red Hat Single Sign-On 7) arises because the IdP-initiated SAML
Authentication bypass in Red Hat Build of Keycloak (and Red Hat Single Sign-On 7) lets an unauthenticated attacker forge
Privilege escalation in Red Hat Build of Keycloak's Dynamic Client Registration (DCR) grants an attacker with low-privil
Mismatched handling of the HTTP/1 absolute-form request authority in Red Hat build of Quarkus and other affected Red Hat
Authorization bypass in the Keycloak Policy Enforcer allows any authenticated user to circumvent all enforced access con
URI normalization bypass in Keycloak's Authorization Services PathMatcher allows authenticated low-privilege users to re
Privilege escalation in Keycloak's Dynamic Client Registration (DCR) component allows attackers with standard user accou
Token exchange in Keycloak bypasses Google Workspace domain allowlist restrictions, enabling any valid Google account ho
Signature-verification bypass in Keycloak (and Red Hat's Keycloak-based products such as Red Hat Single Sign-On 7 and Re
Tenant-restriction bypass in Keycloak's Microsoft identity provider integration allows attackers holding any valid Micro
Session hijacking via SAML assertion replay in Keycloak's SAML broker component allows adjacent-network attackers to aut
Same technique Denial Of Service
View allShare
External POC / Exploit Code
Leaving vuln.today
EUVD-2026-82903
GHSA-6ff9-6jw2-jrgf