Raising troubling questions about the security of America's government websites, more domains ending in .gov have been found hosting links that push porn and malware.

They include the Marin County Transportation Authority, which has has watched its site get hacked at least twice before. In early October the domain forced the shutdown of all California government websites until admins could remove the links. A week after the sites were disinfected, the rogue pointers returned.

On Friday, more than 24 hours after this post from Sunbelt Software first reported the reemergence of the links, the gov site was riddled with at least a dozen pages that, when clicked, redirected users to smut sites. Users then got a messaging saying they had to install a special codec in order to view the content. The codecs contain Trojans that install malware.

By Friday evening in California, the tainted pages were finally removed, and the executive director of the agency apologized for the problem.

The other site actively pushing smut and malware at the time of writing was USAid, a federally operated agency that extends aid to countries recovering from disasters. Perhaps they should attend to their own affairs first.

Over the past several months, the poisoning of search caches belonging to Google and other search engines has emerged as a chief tactic by miscreants in inflating rankings of their malicious websites. At the moment, Google security pros are scrambling to eradicate a flood of malicious links. Problem is, the purveyors of smut and malware are quickly able to taint the cache with a new batch of domains. The whack-a-mole battle finally prompted Google to issue this request for help from its users.

The infections of the gov sites, which are easily documented by these two Google searches (safe to click if you don't mind "porn" in your url, but you probably shouldn't click on any of search results), appear to be yet another attempt to boost the rankings of the malicious sites.

Dianne Steinhauser, executive director of the Marin County Transportation Authority, said she thought the problem was fixed in mid September, after her agency dumped its old web host, StartLogic, and contracted with a new one.

"Even though we quit any web hosting with them, they had a publicly accessible web page with our name on it," she told The Register. "They still had a web service under our name, and that was a complete surprise."

Hackers were able to create the porn- and malware-infested pages by infiltrating StartLogic's system, she said. The pages became inaccessible after her office directed the web host to remove the web-accessible service, she said.

"I am exceptionally apologetic for anyone that was contaminated by virtue of our name," she said.

Attempts to reach representatives of StartLogic and USAid were not successful. ®