Dark Reading is part of the Informa Tech Division of Informa PLC

This site is operated by a business or businesses owned by Informa PLC and all copyright resides with them.Informa PLC's registered office is 5 Howick Place, London SW1P 1WG. Registered in England and Wales. Number 8860726.

Attacks/Breaches

9/25/2014
03:07 PM
50%
50%

'BERserk' Bug Uncovered In Mozilla NSS Crypto Library Impacts Firefox, Chrome

Attackers can exploit the bug to create forged RSA certificates -- it affects versions of Firefox, Thunderbird, Chrome, and SeaMonkey.

A newly discovered critical vulnerability in the Mozilla Network Security Services (NSS) cryptographic library can be abused to create forged RSA certificates.

Mozilla has released updates to fix the issue. According to the company, users on a compromised network could be directed to sites using a fraudulent certificate and mistake them for legitimate sites. This could be used by attackers to trick victims into revealing personal information (like usernames and passwords) or downloading malware.

"The Mozilla NSS library, commonly utilized in the Firefox web browser, can also be found in Thunderbird, Seamonkey, and other Mozilla products," Michael Fey, executive vice president, chief technology officer, and general manager of corporate products for McAfee, part of Intel Security, wrote in a blog post. "Dubbed 'BERserk,' this vulnerability allows for attackers to forge RSA signatures, thereby allowing for the bypass of authentication to websites utilizing SSL/TLS. Given that certificates can be forged for any domain, this issue raises serious concerns around integrity and confidentiality as we traverse what we perceive to be secure websites."

According to Fey, the attack exploits a vulnerability in the passing of ASN.1 encoded messages during signature verification. ASN.1 messages are made up of various parts that are encoded using Basic Encoding Rules (BER) and/or Distinguished Encoding Rules (DER). "This attack exploits the fact that the length of a field in BER encoding can be made to use many bytes of data. In vulnerable implementations, these bytes are then skipped during parsing. This condition enables the attack. This is a variation on the Bleichenbacher PKCS#1 RSA Signature Verification vulnerability of 2006."

Intel Security said it is unaware of any attacks exploiting the issue, which was also discovered and reported independently by the security researcher Antoine Delignat-Lavaud at Inria Paris at team Prosecco.

The following updates have been released for Mozilla client products: Firefox 32.0.3; Firefox for Android 32.0.3; Firefox for Android 31.1.; Firefox ESR 31.1.1; Firefox ESR 24.8.1; Thunderbird 31.1.2; Thunderbird 24.8.1; and SeaMonkey 2.29.1.

Updates are also available for beta and other development versions of these products, according to Mozilla, which advises projects using NSS 3.17 to update to the new 3.17.1 release. Google has already issued an update for Chrome.

The CERT Coordination Center at Carnegie Mellon University (CERT/CC) also released an advisory on the issue.

"This vulnerability is a variant of the Bleichenbacher vulnerability, where unvalidated bytes are allowed in the least significant bytes of the signature," according to CERT. "Mozilla NSS is used by other software products including a number of Linux distributions and packages, Google Chrome, and Google Chrome OS. It is also possible that other cryptographic libraries may have similar vulnerabilities."

"Upon discovery of this issue, the Intel Security ATR [Advanced Threat Research] team notified Mozilla to facilitate the mitigation and resolution of the vulnerability," said James Walter, director of advanced threat research of Intel Security. "We also engaged CERT/CC to ensure that all affected parties are responsibly and effectively notified and given mitigation guidance on this issue, and to review other commonly used cryptographic libraries for similar issues."

Brian Prince is a freelance writer for a number of IT security-focused publications. Prior to becoming a freelance reporter, he worked at eWEEK for five years covering not only security, but also a variety of other subjects in the tech industry. Before that, he worked as a ... View Full Bio
 

Recommended Reading:

Comment  | 
Print  | 
More Insights
Comments
Newest First  |  Oldest First  |  Threaded View
jackdenial
50%
50%
jackdenial,
User Rank: Apprentice
10/23/2018 | 1:12:13 AM
Re: Prior to Update
I totally agreed with your statement that attackers can steal personal information of authorized users like their usernames as well as passwords or downloading malware and BERserk vulnerability also allows attackers to forge RSA signatures. If anyone is facing any issue related to their Mozilla Firefox then I recommend contact with Firefox Support Number
RyanSepe
50%
50%
RyanSepe,
User Rank: Ninja
9/26/2014 | 9:15:02 AM
Prior to Update
I know these were updated by the browser providers but before that when being led to a false site, what were the inconsistencies between the true and the false site, if any?

Or malicious sites so well engineered that you couldn't tell?
COVID-19: Latest Security News & Commentary
Dark Reading Staff 5/28/2020
Stay-at-Home Orders Coincide With Massive DNS Surge
Robert Lemos, Contributing Writer,  5/27/2020
Register for Dark Reading Newsletters
White Papers
Video
Cartoon Contest
Write a Caption, Win a Starbucks Card! Click Here
Latest Comment: Can you smell me now?
Current Issue
How Cybersecurity Incident Response Programs Work (and Why Some Don't)
This Tech Digest takes a look at the vital role cybersecurity incident response (IR) plays in managing cyber-risk within organizations. Download the Tech Digest today to find out how well-planned IR programs can detect intrusions, contain breaches, and help an organization restore normal operations.
Flash Poll
Twitter Feed
Dark Reading - Bug Report
Bug Report
Enterprise Vulnerabilities
From DHS/US-CERT's National Vulnerability Database
CVE-2020-11844
PUBLISHED: 2020-05-29
There is an Incorrect Authorization vulnerability in Micro Focus Service Management Automation (SMA) product affecting version 2018.05 to 2020.02. The vulnerability could be exploited to provide unauthorized access to the Container Deployment Foundation.
CVE-2020-6937
PUBLISHED: 2020-05-29
A Denial of Service vulnerability in MuleSoft Mule CE/EE 3.8.x, 3.9.x, and 4.x released before April 7, 2020, could allow remote attackers to submit data which can lead to resource exhaustion.
CVE-2020-7648
PUBLISHED: 2020-05-29
All versions of snyk-broker before 4.72.2 are vulnerable to Arbitrary File Read. It allows arbitrary file reads for users who have access to Snyk's internal network by appending the URL with a fragment identifier and a whitelisted path e.g. `#package.json`
CVE-2020-7650
PUBLISHED: 2020-05-29
All versions of snyk-broker after 4.72.0 including and before 4.73.1 are vulnerable to Arbitrary File Read. It allows arbitrary file reads to users with access to Snyk's internal network of any files ending in the following extensions: yaml, yml or json.
CVE-2020-7654
PUBLISHED: 2020-05-29
All versions of snyk-broker before 4.73.1 are vulnerable to Information Exposure. It logs private keys if logging level is set to DEBUG.