The flaw, reported in versions earlier than 6.0.5, could crash the application or allow an attacker to launch malicious code, according to an advisory.
Vulnerability monitoring firm Secunia rated the flaw "highly critical" and said the bug could lead to system compromise.
"The AAC (Advanced Audio Coding) file parsing code in iTunes versions prior to 6.0.5 contains an integer overflow vulnerability," Apple’s advisory said. "Parsing (turning script into syntax) a maliciously crafted AAC file could cause iTunes to terminate or potentially execute arbitrary code."
The flaw, first reported to TippingPoint’s Zero Day Initiative, can be resolved by upgrading to the latest version, which is available for download at http://www.apple.com/itunes/download.