Vulnerabilities / Threats
1/4/2013
05:55 PM
Connect Directly
LinkedIn
Twitter
Google+
RSS
E-Mail
50%
50%

Microsoft, Mozilla, Opera Block Unauthorized Digital Certificate

Google alert prompts other browser vendors to block rogue digital certificates.

Microsoft, Mozilla and Opera took steps Thursday to block two unauthorized digital certificates from Turktrust, a Turkish certificate authority, one of which appears to have been used to intercept online communications.

The "intermediate" certificates in question, explained Michael Coates, Mozilla director of security assurance, in a blog post, can be used to conduct a man-in-the-middle (MITM) attack. In so doing, the certificate holder could intercept and access communication on his or her network between a user and any website.

"Such certificates could deceive users into trusting websites appearing to originate from the domain owners, but actually containing malicious content or software," said Coates.

Coates expressed concern that one of the certificates "was used for MITM traffic management of domain names that the customer did not legitimately own or control."

[ Learn more about digital certificates. Read Expired Digital Certificates: A Management Challenge. ]

Microsoft put it more bluntly, stating in its security advisory that it "is aware of active attacks using one fraudulent digital certificate issued by [certificate authority] Turktrust."

Opera's Sigbjorn Vig however was more cautious in his assessment, noting that "the google.com certificate was automatically issued by an over-zealous firewall/proxy, and not used fraudulently in any manner."

Google blocked the two certificates in Chrome browsers last month because it detected one of them being used to impersonate the "*.google.com" domain. It then notified other browser vendors about the issue.

Apple has not yet made a public statement about the incident.

Turktrust said in a statement that the relevant certificates have been revoked and that it has identified the source of the problem, a unique situation the company insists, without providing details. "There is also no evidence of any attack or hacking attempt on our systems, as well as no implication of any malicious usage," the company insisted.

Nonetheless, the incident underscores the fragility of the Internet's trust architecture and offers a reminder of past certificate problems like the hacking of now-defunct certificate authority DigiNotar. Risks include not only the possibility that malicious individuals or groups could misuse digital certificates to intercept online communications but also the possibility that governments could compel local certificate authorities to issue intermediate certificates to facilitate mass online eavesdropping.

Comment  | 
Print  | 
More Insights
Register for Dark Reading Newsletters
White Papers
Cartoon
Current Issue
Flash Poll
Video
Slideshows
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2015-4231
Published: 2015-07-03
The Python interpreter in Cisco NX-OS 6.2(8a) on Nexus 7000 devices allows local users to bypass intended access restrictions and delete an arbitrary VDC's files by leveraging administrative privileges in one VDC, aka Bug ID CSCur08416.

CVE-2015-4232
Published: 2015-07-03
Cisco NX-OS 6.2(10) on Nexus and MDS 9000 devices allows local users to execute arbitrary OS commands by entering crafted tar parameters in the CLI, aka Bug ID CSCus44856.

CVE-2015-4234
Published: 2015-07-03
Cisco NX-OS 6.0(2) and 6.2(2) on Nexus devices has an improper OS configuration, which allows local users to obtain root access via unspecified input to the Python interpreter, aka Bug IDs CSCun02887, CSCur00115, and CSCur00127.

CVE-2015-4237
Published: 2015-07-03
The CLI parser in Cisco NX-OS 4.1(2)E1(1), 6.2(11b), 6.2(12), 7.2(0)ZZ(99.1), 7.2(0)ZZ(99.3), and 9.1(1)SV1(3.1.8) on Nexus devices allows local users to execute arbitrary OS commands via crafted characters in a filename, aka Bug IDs CSCuv08491, CSCuv08443, CSCuv08480, CSCuv08448, CSCuu99291, CSCuv0...

CVE-2015-4239
Published: 2015-07-03
Cisco Adaptive Security Appliance (ASA) Software 9.3(2.243) and 100.13(0.21) allows remote attackers to cause a denial of service (device reload) by sending crafted OSPFv2 packets on the local network, aka Bug ID CSCus84220.

Dark Reading Radio
Archived Dark Reading Radio
Marc Spitler, co-author of the Verizon DBIR will share some of the lesser-known but most intriguing tidbits from the massive report