CVE-2018-11243: PackLinuxElf64::unpack in p_lx_elf.cpp in UPX 3.95 allows remote attackers to cause a denial of service (do...

Security readout for executives and security teams

CVE-2018-11243 is a UPX 3.95 unpacking flaw triggered by a crafted Linux ELF64 file. The known impact is denial of service through a double free, including possible disruption of malware scanning workflows that rely on UPX to unpack files. Exposure is most likely where UPX 3.95 or vulnerable distro-packaged UPX processes untrusted Linux ELF64 files, especially malware analysis, email attachment inspection, upload scanning, or file triage pipelines. Treat as a focused operational risk to file scanning and malware analysis reliability. Prioritize environments processing untrusted binaries, but do not escalate as internet-wide active exploitation based on the provided evidence. Mitigation focus: Inventory systems and scanners that invoke UPX on untrusted files.; Update UPX through vendor-supported packages or upstream guidance.; Prioritize malware scanning and file ingestion environments first..

Prepared

Jun 7, 2026, 13:21 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.