PT-2026-146687

CVE-2026-126401

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Published

2026-11-13

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Updated

2026-11-13

Description by

CVSS 3.1
7.5
High
MetricsAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Fleet before 4.86.2 contains a denial of service vulnerability that allows unauthenticated attackers to exhaust server memory through quadratic XML canonicalization of unsigned SAML responses. Attackers can send a single crafted SAML response with deeply nested elements declaring new namespace prefixes to POST /api/v1/fleet/sso/callback, crashing the Fleet server.
Exploitability
Exploit
Fix
Researchers
Vendors
Affected products
Related identifiers
GHSA-MJRH-3V6H-8G5P
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