Bug 2538858 (CVE-2026-63447)

Summary: CVE-2026-63447 suricata: suricata: Denial of Service via crafted FTP traffic
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: dfreiber, drow, jburrell, vkumar
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Suricata. A remote, unauthenticated attacker can exploit this issue by sending specially crafted File Transfer Protocol (FTP) traffic containing large command sequences, causing the parser to allocate transactions beyond expected limits. Processing this oversized transaction list leads to excessive CPU resource consumption, resulting in degraded packet inspection capabilities and a Denial of Service (DoS).
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-09-22 20:56:35 UTC
Suricata is a network Intrusion Detection System, Intrusion Prevention System and Network Security Monitoring engine. From 8.0.5 until 8.0.6, the FTP parser in src/app-layer-ftp.c can continue allocating transactions after app-layer.protocols.ftp.max-tx is reached while processing one large chunk of FTP command data. The oversized transaction list is repeatedly processed with quadratic complexity after the too_many_transactions event, allowing crafted FTP traffic to degrade packet processing, reduce monitoring visibility, or cause denial of service. This issue is fixed in version 8.0.6.