CWE-409
AllowedImproper Handling of Highly Compressed Data (Data Amplification)
Abstraction: Base · Status: Incomplete
The product does not handle or incorrectly handles a compressed input with a very high compression ratio that produces a large output.
151 vulnerabilities reference this CWE, most recent first.
GHSA-XV6H-R36F-3GP5
Vulnerability from github – Published: 2026-03-18 06:31 – Updated: 2026-03-18 20:19A flaw was found in Keycloak. An unauthenticated remote attacker can trigger an application level Denial of Service (DoS) by sending a highly compressed SAMLRequest through the SAML Redirect Binding. The server fails to enforce size limits during DEFLATE decompression, leading to an OutOfMemoryError (OOM) and subsequent process termination. This vulnerability allows an attacker to disrupt the availability of the service.
{
"affected": [
{
"package": {
"ecosystem": "Maven",
"name": "org.keycloak:keycloak-saml-adapter-core"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "26.5.4"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.keycloak:keycloak-saml-core"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "26.5.4"
}
],
"type": "ECOSYSTEM"
}
]
},
{
"package": {
"ecosystem": "Maven",
"name": "org.keycloak:keycloak-services"
},
"ranges": [
{
"events": [
{
"introduced": "0"
},
{
"fixed": "26.5.4"
}
],
"type": "ECOSYSTEM"
}
]
}
],
"aliases": [
"CVE-2026-2575"
],
"database_specific": {
"cwe_ids": [
"CWE-409"
],
"github_reviewed": true,
"github_reviewed_at": "2026-03-18T20:19:33Z",
"nvd_published_at": "2026-03-18T04:17:16Z",
"severity": "MODERATE"
},
"details": "A flaw was found in Keycloak. An unauthenticated remote attacker can trigger an application level Denial of Service (DoS) by sending a highly compressed SAMLRequest through the SAML Redirect Binding. The server fails to enforce size limits during DEFLATE decompression, leading to an OutOfMemoryError (OOM) and subsequent process termination. This vulnerability allows an attacker to disrupt the availability of the service.",
"id": "GHSA-xv6h-r36f-3gp5",
"modified": "2026-03-18T20:19:33Z",
"published": "2026-03-18T06:31:20Z",
"references": [
{
"type": "ADVISORY",
"url": "https://nvd.nist.gov/vuln/detail/CVE-2026-2575"
},
{
"type": "WEB",
"url": "https://github.com/keycloak/keycloak/issues/46372"
},
{
"type": "WEB",
"url": "https://github.com/keycloak/keycloak/commit/4f90ef67f698dfb45df0d2f4981271a7c8b47f04"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:3947"
},
{
"type": "WEB",
"url": "https://access.redhat.com/errata/RHSA-2026:3948"
},
{
"type": "WEB",
"url": "https://access.redhat.com/security/cve/CVE-2026-2575"
},
{
"type": "WEB",
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2440149"
},
{
"type": "PACKAGE",
"url": "https://github.com/keycloak/keycloak"
}
],
"schema_version": "1.4.0",
"severity": [
{
"score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L",
"type": "CVSS_V3"
}
],
"summary": "Keycloak: Denial of Service due to excessive SAMLRequest decompression"
}
No mitigation information available for this CWE.
No CAPEC attack patterns related to this CWE.