I found this on Yahoo news today (via the AFP):

HANOI (AFP) – Vietnam has rejected accusations by Internet giant Google that Vietnamese computer users have been spied on and political blogs hacked into.

The US-based firm last week said infected machines had been used both to spy on their owners as well as to attack blogs containing messages of political dissent.

"These are groundless opinions," Nguyen Phuong Nga, spokeswoman for the Ministry of Foreign Affairs, told AFP.

Vietnam has "specific regulations against computer viruses, harmful software and for ensuring information security and secrecy," she said in comments received over the weekend.

Google said the malicious software infected computers of users who downloaded Vietnamese language software, and possibly other legitimate software, that was altered to infect the machines.

Leading Internet security firm McAfee said perpetrators of the Vietnamese attacks "may have political motivations and may have some allegiance to the government of the Socialist Republic of Vietnam".

Google announced last month it was redirecting mainland Chinese users to an uncensored site in Hong Kong, making good on an earlier pledge not to go along with the Communist Party government's censorship rules.

Its decision to defy Beijing was based on what it called concerns over censorship and cyberattacks it said originated from China.

Analysts, rights groups and diplomats say the human rights situation in Vietnam has been worsening.

The country's restrictions on news media and Internet sites such as Facebook threatened Vietnam's rapid economic progress, Western donors said in December.

That Vietnam is now being accused of spying on political dissonants comes as a bit of a surprise to me.  Vietnam has been known historically for communism and socialism, as well as clamping down on human rights, but in the past two decades has greatly liberalized its economy and trade practices.  It boasts a very high rate of GDP growth (over 5% for 2009) and the United States has formally re-established relations with the country.  I guess that shows what I know, however.  According to the CIA World Fact Book, Vietnam is still officially a communist state and the country’s official name is the Socialist Republic of Vietnam.  The ruling party is the Communist Party of Vietnam while opposition groups are the Democratic Party of Vietnam, People’s Democratic Party Vietnam, and the Alliance for Democracy.  These groups advocate democracy but are not recognized by the government.

I don’t have any other information to go on, but from the looks of it, Google is complaining that some of their software was modified such that when installed, it allowed the modifier to monitor the traffic of the person using the browser.  My guess is that there is a localized version of some Google software, possibly Google Chrome, that was pirated, reverse engineered and modified.  Either that, or malicious software in the form of localized Vietnamese versions of antivirus flipped the computers into a botnet.

In any case, either the browsing history of the person using the software was redirected or sniffed, or possibly the bots launched a denial-of-service attack on Vietnamese versions of some of Google’s social networking sites, BlogSpot and YouTube being the most obvious targets.  In this sense, it bears a strong resemblance to the denial-of-service attacks on the various social network sites last year launched against the blogger Cyxymu.  As in that case, state sponsorship is not always required in order to do something like this… but it helps.

I only have a theory, but my guess is that websites or social networking pages from those services, run by one of the opposition parties mentioned above, suffered some DOS attacks and either brought them down or attempted to bring them down.  Whether or not they succeeded is unclear from the article but this does fit a pattern we see recurring again and again.