Cyber Saturday—As Blockchain Week Kicks Off, Remember The DAO – 网络星期六作为链链周开始，记住刀

Smacked down. Symantec’s market value collapsed by a third after the antivirus maker disclosed an internal investigation prompted by a whistleblower. “The Company’s financial results and guidance may be subject to change based on the outcome of the Audit Committee investigation,” Symantec said in its statement accompanying its annual earnings report. It’s unclear what the investigation concerns, although the company clarified that it is not related to a security breach.

Equifax…again. Just when you thought the credit bureau had moved on from its data breach, Equifax said in an SEC filing that tens of thousands of more consumers records were compromised in its 2017 data breach. Hackers accessed photos of 38,000 driver’s licenses, 12,000 Social Security or taxpayer ID cards, 3,200 passports, and 3,000 other ID documents, the company said. And so the blast radius continues to widen.

Secret tweets. Twitter is reportedly testing end-to-end encrypted Direct Messages. A computer science student noticed the experimental feature embedded in a package of code for Twitter’s Android application, the sort of place where tech companies tend to drop to-be-released updates early. It remains to be seen whether the company will roll the feature out publicly as rivals, like Facebook, already have.

Mixed signals. Due to an idiosyncrasy in the way Mac operating systems handle app notifications, messages sent via the encrypted chat app Signal appear to be recorded indefinitely in the memory of Apple computers, security researchers have warned. The bug could cause a log of conversations that had supposedly self-destructed or been deleted to persist.

Fool me three times…

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Have we learned nothing? Despite fixes being available, thousands of businesses are still downloading vulnerable versions of Apache Struts, the software hackers exploited to loot Equifax. While it’s hard to say whether companies are using this code in production, it is likely that many are. One would think that businesses would have learned from Equifax’s mistake by now. Apparently not.

How Relying on Oil Makes Us More Vulnerable to Cyberattacks, by Nathan Sproul

How China’s Laser Attacks on the U.S. Military Could Cause a Serious Conflict, by Andrew Shear

Facebook Found 3,000 Russia-Linked Election Ads. Now House Democrats Are Planning to Release Them, by Natasha Bach

Undetectable Commands for Apple’s Siri and Amazon’s Alexa Raise Serious Security Risks, by Chris Morris

The U.S. Navy Revives Second Fleet to Counter Russian Aggression, by David Z. Morris

You can’t handle the truth. A recently published study conducted at Harvard Business School found that online ads were less effective on people who were told they were targeted based on tracking activity on other websites. Advertisers who disclose their privacy-intrusive methods turn off consumers. “If you track people across the internet, as Facebook routinely does, and admit that fact to them, the transparency will poison the resulting ads,” writes The Intercept.