It only took five hours to close a critical vulnerability in Signal's desktop client

Researchers and developers working in harmony. It can be done!

A critical vulnerability found in the desktop version of secure messaging app Signal was patched less than five hours after disclosure to the developers, a rapid response that’s earned some plaudits from observers.

Security researchers detailed a remote code execution flaw in the Signal desktop application across Windows, Mac OSX and Linux operating systems. A hacker could execute code on a targeted system just by sending a message to the victim because Signal’s desktop app failed to sanitize specific HTML tags that can inject HTML code into remote chat windows.

“The critical thing here was that it didn’t require any interaction form[sic] the victim, other than simply being in the conversation,” the researchers wrote. “Anyone can initiate a conversation in Signal, so the attacker just needs to send a specially crafted URL to pwn the victim without further action. And it is platform independent!”

Joshua Lund, a developer at Signal, commented that “exploiting this requires the attacker to first manually place malware (a malicious JavaScript file) on your computer or on a Samba network share that your computer is already connected to.”

The problem was first discovered late last Thursday. Researchers disclosed the issue to Signal’s developers on Friday around 1 p.m. By 5 p.m., a security update — version 1.10.1 — was published.

Open Whisper Systems, which develops Signal, did not respond to a request for comment.

Signal’s applications and technology have been gaining prominence of late. Microsoft’s adoption of Signal’s encryption protocol followed similar moves by Facebook, WhatsApp and Google. The technology is used chats for billions of users.

The Signal Foundation, a newly founded nonprofit, recently took in $50 million from WhatsApp founder Brian Acton.

Government

• FBI officials say AI is bolstering adversaries, emphasizing need to focus on cyber basics, patching

• Feds accuse China of ‘systematic’ distillation of U.S. AI models

• CIA’s Michael Ellis says cyber intelligence is changing how the agency operates

• Jail time for Maine child in 764 marks turning point in federal law enforcement

Technology

• FCC proposes public scorecard to rate telecoms on anti-robocall efforts

• Pegasus, NoviSpy variant spyware found on devices of Serbian activists

• Wyden seeks upgraded NSA security guidance on commercial VPN use

• The Collective Cyber Defense letter wrote your next vendor questionnaire

Threats

• Chinese espionage groups swarm to exploit triple-link chain of zero-days

• Russian national extradited to US for alleged involvement in bank-account takeover scheme

• Attackers exploit zero-days in consistently besieged SonicWall product

• Dogged Russia-based botnet dismantled after 23-year run

Policy

• Whistleblower says USPS deploying new, ‘untested’ IT systems governing mail-in ballots

• ‘Watershed 250’ test program in Texas looks to private sector for water cybersecurity help

• Former sexual abuse victims say Grok used their images, videos to train deepfake capabilities

• Cyber threats nudge Trump to sign executive order on foreign equipment in U.S. energy infrastructure