Google last week warned website owners that digital certificates from Chinese certificate authority WoSign and its subsidiary StartCom will no longer be trusted starting with Chrome 61.
Mozilla, Apple and Google last year decided to revoke trust in certificates from WoSign and StartCom as a result of more than a dozen incidents and issues brought to the attention of the web browser community since January 2015.
Problems include backdating certificates to bypass restrictions, issuing certificates without authorization, and misleading browser vendors about WoSign’s acquisition of StartCom and their relationship.
Google started taking action against the firms in late January 2017, with the release of Chrome 56, which no longer accepted certificates issued by WoSign or StartCom after October 21, 2016.
In order to minimize impact on website owners, Google has been restricting trust to popular hostnames based on the Alexa Top 1 Million list. This whitelist has been gradually reduced and starting with Chrome 61 it will be removed completely. Chrome 61 will reach the Developer channel in the coming weeks, the Beta channel in late July 20, and the Stable channel in mid-September.
“Sites still using StartCom or WoSign-issued certificates should consider replacing these certificates as a matter of urgency to minimize disruption for Chrome users,” warned Devon O’Brien of the Chrome Security Team.
Apple and Mozilla have decided to ban WoSign and StartCom for at least one year, but Google has not specified for how long it plans on distrusting certificates from these companies.
The certificate authorities had several meetings with browser vendors, changed leadership and promised to completely separate WoSign from StartCom, but they did not convince Apple, Google and Mozilla. Apple was the first to announce plans to revoke trust in their certificates, followed by Mozilla, which justified its decision by arguing that the firms were deceptive.
Related Reading: Google Stops Trusting Symantec-Issued Certificates
Related Reading: Mandatory Certificate Authority Authorization Checks Will Boost Domain Security
Related Reading: Let’s Encrypt Issues 15,000 Fraudulent “PayPal” Certificates Used for Cybercrime

Eduard Kovacs (@EduardKovacs) is a contributing editor at SecurityWeek. He worked as a high school IT teacher for two years before starting a career in journalism as Softpedia’s security news reporter. Eduard holds a bachelor’s degree in industrial informatics and a master’s degree in computer techniques applied in electrical engineering.
More from Eduard Kovacs
- Industrial Giant ABB Confirms Ransomware Attack, Data Theft
- Zyxel Firewalls Hacked by Mirai Botnet
- New Russia-Linked CosmicEnergy ICS Malware Could Disrupt Electric Grids
- Drop in Insider Breaches Drives Decline in Intrusions at OT Organizations
- Zero-Day Vulnerability Exploited to Hack Barracuda Email Security Gateway Appliances
- OAuth Vulnerabilities in Widely Used Expo Framework Allowed Account Takeovers
- New Honeywell OT Cybersecurity Solution Helps Identify Vulnerabilities, Threats
- Rheinmetall Says Military Business Not Impacted by Ransomware Attack
Latest News
- Industrial Giant ABB Confirms Ransomware Attack, Data Theft
- Organizations Worldwide Targeted in Rapidly Evolving Buhti Ransomware Operation
- Google Cloud Users Can Now Automate TLS Certificate Lifecycle
- Zyxel Firewalls Hacked by Mirai Botnet
- Watch Now: Threat Detection and Incident Response Virtual Summit
- NCC Group Releases Open Source Tools for Developers, Pentesters
- Memcyco Raises $10 Million in Seed Funding to Prevent Website Impersonation
- New Russia-Linked CosmicEnergy ICS Malware Could Disrupt Electric Grids
