Spectre, Meltdown researchers unveil 7 more speculative execution attacks

Systemic analysis reveals a range of new issues and a need for new mitigations.

Spectre, Meltdown researchers unveil 7 more speculative execution attacks

Enlarge (credit: Aurich Lawson / Getty Images)

Back at the start of the year, a set of attacks that leveraged the speculative execution capabilities of modern high-performance processors was revealed. The attacks were named Meltdown and Spectre. Since then, numerous variants of these attacks have been devised. In tandem, a range of mitigation techniques has been created to enable at-risk software, operating systems, and hypervisor platforms to protect against these attacks.

A research team—including many of the original researchers behind Meltdown, Spectre, and the related Foreshadow and BranchScope attacks—has published a new paper disclosing yet more attacks in the Spectre and Meltdown families. The result? Seven new possible attacks. Some are mitigated by known mitigation techniques, but others are not. That means further work is required to safeguard vulnerable systems.

The previous investigations into these attacks has been a little ad hoc in nature; examining particular features of interest to provide, for example, a Spectre attack that can be performed remotely over a network, or Meltdown-esque attack to break into SGX enclaves. The new research is more systematic, looking at the underlying mechanisms behind both Meltdown and Spectre and running through all the different ways the speculative execution can be misdirected.

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Windows 10 October 2018 Update is back, this time without deleting your data

Microsoft is opening up about some of its testing procedures, too.

This message, shown during Windows upgrades, is going to be salt in the wound.

Enlarge / This message, shown during Windows upgrades, is going to be salt in the wound.

Just over a month since its initial release, Microsoft is making the Windows 10 October 2018 Update widely available today. The update was withdrawn shortly after its initial release due to the discovery of a bug causing data loss.

New Windows 10 feature updates use a staggered, ramping rollout, and this (re)release is no different. Initially, it'll be offered only to two groups of people: those who manually tell their system to check for updates (and that have no known blocking issues due to, for example, incompatible anti-virus software), and those who use the media-creation tool to download the installer. If all goes well, Microsoft will offer the update to an ever-wider range of Windows 10 users over the coming weeks.

For the sake of support windows, Microsoft is treating last month's release as if it never happened; this release will receive 30 months of support and updates, with the clock starting today. The same is true for related products; Windows Server 2019 and Windows Server, version 1809, are both effectively released today.

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Another Windows 0-day flaw has been published on Twitter

And on GitHub there’s a proof-of-concept that’ll render your system unbootable.

SandboxEscaper, a researcher who back in August tweeted out a Windows privilege escalation bug, has published another unpatched Windows flaw on Twitter.

The new bug has some similarities to the previous bug. Windows services usually run with elevated privileges. Sometimes they perform actions on behalf of a user, and to do this they use a feature called impersonation. These services act as if they were using a particular user's set of privileges. After they've finished that action, they revert to their normal, privileged identity.

Both this bug and SandboxEscaper's previous bug depend on improper use of impersonation—specifically, the services in question (last time it was Task Scheduler, this time it's the "Data Sharing Service") revert their impersonation too quickly and end up performing some actions with elevated privileges when they should in fact have been impersonated. The last bug allowed one file to be written over another. In this case, it's a call to delete a file that is improperly impersonated, ultimately giving regular unprivileged user the ability to delete any file on the system, even those that they should have no access to.

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Apple, Google, Microsoft, and Mozilla come together to end TLS 1.0

Almost everyone has now migrated to TLS 1.2, and a few have moved to TLS 1.3.

A green exterior door is sealed with a padlock.

Enlarge (credit: Indigo girl / Flickr)

Apple, Google, Microsoft, and Mozilla have announced a unified plan to deprecate the use of TLS 1.0 and 1.1 early in 2020.

TLS (Transport Layer Security) is used to secure connections on the Web. TLS is essential to the Web, providing the ability to form connections that are confidential, authenticated, and tamper-proof. This has made it a big focus of security research, and over the years, a number of bugs that had significant security implications have been found in the protocol. Revisions have been published to address these flaws.

The original TLS 1.0, heavily based on Netscape's SSL 3.0, was first published in January 1999. TLS 1.1 arrived in 2006, while TLS 1.2, in 2008, added new capabilities and fixed these security flaws. Irreparable security flaws in SSL 3.0 saw support for that protocol come to an end in 2014; the browser vendors now want to make a similar change for TLS 1.0 and 1.1.

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