This indicates an attack attempt to exploit a Denial of Service vulnerability in IBM Notes.
The vulnerability is due to an error when handling malformed HTML file. A remote attacker may be able to exploit this to cause a denial of service condition on the affected system.
IBM Notes 9.0.1 to 9.0.1 FP8IF1
IBM Notes 9.0 to 9.0 IF4.
IBM Notes 8.5.3 to 8.5.3 FP6 IF13.
IBM Notes 8.5.2 to 8.5.2 FP4 IF3.
IBM Notes 8.5.1. to 8.5.1 FP5 IF5.
IBM Notes 8.5 release
Denial of Service: Remote attackers can crash vulnerable systems.
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