FlashbackB

YARA detection rule by Unknown · Unknown

OSX.Flashback.B

import "hash"
rule FlashbackB
{
    meta:
        description = "OSX.Flashback.B"
        xprotect_rule = true
    condition:
        filesize <= 200000 and (
            hash.sha1(0, filesize) == "fd7810b4458a583cca9c610bdf5a4181baeb2233" or
            hash.sha1(0, filesize) == "7004aec6b8193b8c3e8032d720dc121b23b921b7" or
            hash.sha1(0, filesize) == "b87a94ddd93fc036215056fbbed92380eefcadc2" or
            hash.sha1(0, filesize) == "3f40c8d93bc7d32d3c48eedacc0cd411cf273dba"
        ) or
        filesize <= 300000 and (
            hash.sha1(0, filesize) == "e266dd856008863704dd9af7608a58137d8936ba" or
            hash.sha1(0, filesize) == "7b6d5edf04a357d123f2da219f0c7c085ffa67fc" or
            hash.sha1(0, filesize) == "284484b13022e809956bb20b6ba741bd2c0a7117"
        )
}

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

b563b2c8-a48f-466d-bfd4-b9d4616dd10d

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Executable code, not a declarative rule

This submission is arbitrary [[ currentRule.format ? currentRule.format.toUpperCase() : '' ]] code, not a declarative detection rule — review it as you would any script before running it, and note that it cannot be safely aggregated or auto-executed alongside YARA/Sigma/Suricata/CRS rules.

Rejected pattern present

[[ reason ]]

What does this mean?

Format & documentation suggestions

Not a security issue — this rule is valid and was accepted as-is. These are optional fields/conventions its own format recommends, mainly affecting its quality score and how well it documents itself for other reviewers.

[[ reason ]]

What do these messages mean?

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

[[ currentRule.title ]]

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