Bug 2573040 (CVE-2026-128238)

Summary: CVE-2026-128238 scapy: scapy: Denial of Service via deeply nested ASN.1 structures
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: rhel-process-autobot, watson-tool-maintainers, yguenane
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in Scapy. An unauthenticated remote attacker could cause a Denial of Service (DoS) by sending specially crafted network packets containing deeply nested ASN.1 (Abstract Syntax Notation One) data structures. The parser fails to properly limit recursion depth when decoding these structures, triggering an unhandled error that crashes the parsing application.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-13 09:46:25 UTC
Scapy before 2.8.0 contains an uncontrolled recursion vulnerability in the BER/ASN.1 decoder in scapy/asn1/ber.py that allows unauthenticated remote attackers to crash parsing applications. Attackers can send a single 833-byte packet with 250 nested ASN.1 SEQUENCE structures to trigger an unhandled RecursionError, terminating TLS, SNMP, X.509, or LDAP parsers even with safe=True.