Adobe Systems released emergency security patches to fix a vulnerability in versions of Flash Player.
Cybersecurity company Kaspersky Lab revealed that a bug related to Flash compromised jpic.gov.sy, a Syrian Justice Ministry website that was set up to receive complaints about law violations.
According to Adobe, the vulnerability detected in Flash helped attackers gain control of affected computer systems, thereby compromising the security of those who visited the site.
The company, however, said that no other attacks as a result of the Flash bug have been reported.
According to Kaspersky security researchers, the Syrian website attack was a type of watering-hole campaign wherein hackers compromise the systems of individuals by targeting and infecting the sites which they frequent.
The researchers believe the attack was designed to spy on Syrian dissidents complaining about the government.
Vyacheslav Zakorzhevsky, manager of the vulnerability research group at Kaspersky Lab, said: "Although we've only seen a limited number attempts to exploit this vulnerability, we're strongly recommending users to update their versions of Adobe Flash Player software.
"It is possible that once information about this vulnerability becomes known, criminals will try to reproduce these new exploits or somehow get the existing variants and use them in other attacks."