This indicates a possible attempt to exploit one of several vulnerabilities in Mozilla Firefox, Thunderbird and SeaMonkey.
The vulneabilities are a result of memory corruption. They may allow a remote attacker to crash the application, causing a Denial of Service.
Firefox 188.8.131.52 and earlier.
Thunderbird 184.108.40.206 and earlier.
Seamonkey 1.1.5 and earlier.
Denial of Service
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