"It’s time we showed another example of how dangerous these URI handler vulnerabilities can be…" said the trio, detailing the flaws on the xs-sniper.com website.
The first flaw is due to an input validation error in the "ini=" parameter supplied via "aim://" URIs. The vulnerability could be exploited by a remote attacker to take control of a targeted system, according to Secunia.
The second vulnerability occurs within the processing of "aim://" URIs in the aim.dll plugin. The flaw can be exploited by attackers by tricking a user into following a specially crafted "aim://" URI file, according to the Danish vulnerability clearinghouse.
Secunia ranked the flaws, both of which exist in Trillian Basic 3.1.6.0, as "highly critical," meaning that they can be exploited from a remote location.
FrSIRT ranked both flaws as "critical." A Trillian representative could not immediately be reached for comment.
Rios told SCMagazine.com that he and his colleagues have been researching URI flaws for a year and found that they are "rampant."
"We’ve basically encountered a ‘perfect storm’ when it comes to URI handlers. Most developers don’t realize that by registering a URI handler with Windows, they are significantly increasing their attack surface," he said via email.
"URI handlers can allow remote access to applications on a user’s system. If an application isn’t coded properly, attackers can abuse this remote access to compromise a system."
Meanwhile, researcher Rajesh Sethumadhavan released proof-of-concept buffer overflow exploit code for a flaw in Yahoo Messenger version 8.1. The code can be used for a DoS attack when Yahoo loads a specially crafted address book entry.
Sethumadhavan said on Monday that the flaw was discovered on 10 April.
An attacker can take advantage of the flaw by sending a specially crafted address and using a social engineering attack to get a victim to place the mouse over the imported address.
A Yahoo representative could not immediately be reached for comment.
Don Montgomery, vice president of marketing at Akonix, told SC Magazine that vulnerabilities on IM platforms are a growing problem.
"IM gets adopted more widely at home and at work now, and the bigger the network, the bigger the problem is," he said. "[Home users] are less likely to be secure and less likely to be on a protected network. They’re probably on broadband or cable."