Adobe Reader sandbox popped says Google researcher

Yet another reason to make sure you've patched promptly and properly


The Acrobat Reader Windows sandbox contains a vulnerability that could allow attackers to break out and gain higher privileges, Google security bod James Forshaw claims.

The NTFS junction attack is a "race condition" in the handling of the MoveFileEx call hook Forshaw said.

While unpatched, subsequent September updates made the flaw very difficult to exploit.

"While this bug technically isn't fixed, a defence in depth change in 11.0.9 effectively made this difficult if not impossible to exploit," Forshaw said in an advisory for version 11.0.8.

It was a flaw similar to a previous bug in NtSetInformationFile but different because it exploited a time of check to time of use race, a feat possible only because the broker opened the file rather than the sandboxed process, he said.

"While the function resolves the location of the source and destination and ensures they are within the policy there is a timing race once the function calls into the MoveFileEx function in the broker. This race can be won by the sandboxed process by using an OPLOCK to wait for the point where the MoveFileEx function opens the original file for the move. This allows code in the sandbox to write an arbitrary file to the file system.

Forshaw attached a proof-of-concept which on successful exploitation would create a file named 'abc' on the desktop. ®

Broader topics


Other stories you might like

  • Experts: AI should be recognized as inventors in patent law
    Plus: Police release deepfake of murdered teen in cold case, and more

    In-brief Governments around the world should pass intellectual property laws that grant rights to AI systems, two academics at the University of New South Wales in Australia argued.

    Alexandra George, and Toby Walsh, professors of law and AI, respectively, believe failing to recognize machines as inventors could have long-lasting impacts on economies and societies. 

    "If courts and governments decide that AI-made inventions cannot be patented, the implications could be huge," they wrote in a comment article published in Nature. "Funders and businesses would be less incentivized to pursue useful research using AI inventors when a return on their investment could be limited. Society could miss out on the development of worthwhile and life-saving inventions."

    Continue reading
  • Declassified and released: More secret files on US govt's emergency doomsday powers
    Nuke incoming? Quick break out the plans for rationing, censorship, property seizures, and more

    More papers describing the orders and messages the US President can issue in the event of apocalyptic crises, such as a devastating nuclear attack, have been declassified and released for all to see.

    These government files are part of a larger collection of records that discuss the nature, reach, and use of secret Presidential Emergency Action Documents: these are executive orders, announcements, and statements to Congress that are all ready to sign and send out as soon as a doomsday scenario occurs. PEADs are supposed to give America's commander-in-chief immediate extraordinary powers to overcome extraordinary events.

    PEADs have never been declassified or revealed before. They remain hush-hush, and their exact details are not publicly known.

    Continue reading
  • Stolen university credentials up for sale by Russian crooks, FBI warns
    Forget dark-web souks, thousands of these are already being traded on public bazaars

    Russian crooks are selling network credentials and virtual private network access for a "multitude" of US universities and colleges on criminal marketplaces, according to the FBI.

    According to a warning issued on Thursday, these stolen credentials sell for thousands of dollars on both dark web and public internet forums, and could lead to subsequent cyberattacks against individual employees or the schools themselves.

    "The exposure of usernames and passwords can lead to brute force credential stuffing computer network attacks, whereby attackers attempt logins across various internet sites or exploit them for subsequent cyber attacks as criminal actors take advantage of users recycling the same credentials across multiple accounts, internet sites, and services," the Feds' alert [PDF] said.

    Continue reading

Biting the hand that feeds IT © 1998–2022