Adobe is preparing a patch for a zero-day vulnerability affecting Chrome, Linux, OS X and all Windows systems, including Windows 10, that is being actively exploited.
Adobe said in a security advisory on Tuesday that it's been made aware of a "critical vulnerability" in Flash Player 184.108.40.206 and earlier that could "cause a crash and potentially allow an attacker to take control of the affected system".
The company warned that all versions of Windows are being targeted using the flaw.
"Adobe is aware of reports that CVE-2016-1019 is being actively exploited on systems running Windows 10 and earlier with Flash Player version 220.127.116.116 and earlier," the firm said.
"A mitigation introduced in Flash Player 18.104.22.168 currently prevents exploitation of this vulnerability, protecting users running Flash Player 22.214.171.124 and later."
The firm also recommended updating all browsers installed on machines to mitigate the risk.
The scope of the platforms being targeted originally focused just on Windows XP and Windows 7, but clearly new information has come to light.
The company thanked Kafeine of Proofpoint, Genwei Jiang of FireEye and Clement Lecigne of Google for bringing the CVE-2016-1019 Flash exploit to its attention.
Adobe is readying a patch which is due to be released on 7 April. In the meantime, users should make sure their version of Flash is as up-to-date as possible.
Adobe was forced last month to release an emergency patch for yet another critical vulnerability that could allow an attacker to take control of affected systems.
These flaws could soon, but probably won't, become a thing of the past, though, as Adobe is encouraging developers to ditch Flash in favour of HTML5.
To hear more about security challenges, the threats they pose and how to combat them, sign up for V3 sister site Computing's Enterprise Security and Risk Management conference taking place on 24 November.
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