Skype has release twin hotfixes for a flaw that caused instance messages to be sent to the wrong contacts.
The fixes released today patch the flaw on Skype versions for Windows and Linux. Mac users will need to wait for release 18.104.22.1687.
At least one user reported the flaw on Skype forums two weeks ago. Users reported that messages were delivered to contacts at random but appeared to have been sent normally in the program's history.
Leonas Sendrauskas, an engineer at the Microsoft company, said in a blog post that the flaw arose when Skype crashes during an IM session.
"[This] may in some cases result in the last IM entered or sent prior to the crash being delivered to a different IM contact after the Skype client is rebooted or logged in as a new user," Sendrauskas said.
"Although we cannot determine precisely how many users may have been affected by this error, we believe the number is small given the very specific circumstances under which the error occurs."
The flaw affected updated Skype versions 5.10 for Windows, 5.8 for Mac, 4.0 for Linux, and 1.2 for Windows Phone.