Critical Cryptographic Flaw in GnuTLS: DTLS Vulnerability Exposed
Summary
ALPINE-CVE-2020-11501: GnuTLS 3.6.x before 3.6.13 uses incorrect cryptography for DTLS. Affects gnutls versions < 3.6.8-r1. Fixed in 3.6.8-r1. How to fix ↓
Check if this vulnerability affects your application
Upload a manifest or SBOM and we'll show whether you're affected, plus every other risky package in the same scan.
No signup required · Results in about 60 seconds
Habilume
Habit tracker with a companion that grows with you
Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
Background
GnuTLS is an open-source implementation of the TLS and SSL protocols, providing cryptographic functions to secure communications over networks. It is widely used in various applications and systems to ensure data integrity and confidentiality. However, a significant vulnerability has been identified in versions 3.6.x prior to 3.6.13, which affects the security of the Datagram Transport Layer Security (DTLS) protocol, potentially compromising the security of applications relying on GnuTLS for secure communications.
Vulnerability Detail
The vulnerability arises from incorrect cryptographic practices in GnuTLS 3.6.x before version 3.6.13. Specifically, the DTLS client erroneously uses a fixed value of 32 '\0' bytes instead of a random value during the negotiation process. This flaw was introduced due to an error in a commit made on October 6, 2017, and affects all versions starting from 3.6.3. The lack of randomness undermines the security guarantees of the DTLS protocol, making it susceptible to various attacks, including man-in-the-middle attacks, where an attacker could intercept and manipulate communications.
How To Fix
Minimum fixed version
3.6.8-r1
This is the first release that contains the fix.
sudo apk add --upgrade gnutlsTip — Not sure which version your app runs? Vulert can match this fix to it. Scan free →
Workaround
As a temporary workaround, users can limit the exposure of applications using GnuTLS by implementing additional security measures, such as using alternative secure communication libraries or restricting access to vulnerable services until the update is applied.
Conclusion
The GnuTLS vulnerability identified as CVE-2020-11501 poses a significant risk to applications relying on DTLS for secure communications. It is crucial for users to update to the patched version 3.6.13 or later to mitigate this risk. Additionally, utilizing tools like Vulert can help in monitoring and managing vulnerabilities effectively.
See every vulnerability recorded for gnutls →
FAQ
The CVSS score of this vulnerability is 7.4, indicating a high severity level.
GnuTLS versions 3.6.3 to 3.6.12 are affected by this vulnerability.
You can use the Vulert playground at Vulert Scanner to check if your application is affected by this vulnerability without requiring any signup.
The vulnerability can lead to compromised security in applications using DTLS, allowing attackers to intercept and manipulate secure communications.
Yes, Vulert can monitor and alert in real-time for open-source vulnerabilities in your software using just a manifest file like package-lock.json.
References
Related vulnerabilities
Recent vulnerabilities recorded for gnutls.
Habilume
Habit tracker with a companion that grows with you
Complete habits, earn Lume Points, and watch your Lume grow as you stay consistent.
