Last month, NATO troops found SA-14 missile parts in Afghanistan. This raises the fear that Iran is supplying the shoulder fired anti-aircraft missile to the Taliban. But Iran has not distributed that missile to any of its allies, including Hezbollah in Lebanon and Hamas in Gaza. Seven years ago, Israel feared that Hezbollah would get the SA-14, but this has not yet come to pass. It was only two years ago that the Taliban first used the older SA-7, in an unsuccessful attack against a foreign aircraft. Iran, in general, does not like the Taliban. In the 1990s, the Taliban, and their al Qaeda allies, murdered and terrorized Afghan Shia. Despite that hatred, some radical factions in Iran have provided al Qaeda and the Taliban with some assistance.
The SA-14 is 4.7 feet long, weighs 35 pounds and has a max range of 4.1 kilometers. It can't hit anything above 7,100 feet and has a 3 pound warhead. It entered service in 1974 and is called the Strela-3 by the Russians. The primary advantage of the SA-14 is a better sensor, which can more easily defeat countermeasures and is more reliable.
The SA-7 itself is about 4.6 feet long, weighs 33 pounds and has a max range of 3.2-4.2 kilometers (depending on the model). It can't hit anything above 6,900 feet and has a 3 pound warhead (with one pound of explosives). It entered service in 1968 and is called the Strela-2. The earlier Strela-1 was a real piece of junk that was quickly succeeded by the Strela-2.
Against larger transports, the Strela will more likely damage than destroy. But one and two engine commercial aircraft, and helicopters, are very vulnerable. Helicopters in Afghanistan and Iraq are most vulnerable, and carry countermeasures.