CVE-2015-7940: Infoleak
Bouncy Castle could allow a remote attacker to obtain sensitive information. An attacker could exploit this vulnerability using an invalid curve attack to extract private keys used in elliptic curve cryptography and obtain sensitive information.
Other sources
The Bouncy Castle Java library before 1.51 does not validate a point is withing the elliptic curve, which makes it easier for remote attackers to obtain private keys via a series of crafted elliptic curve Diffie Hellman (ECDH) key exchanges, aka an "invalid curve attack."
— Launchpad
Affected Software
Remediation
Event History
Frequently Asked Questions
What is CVE-2015-7940?
CVE-2015-7940 is a vulnerability in the Bouncy Castle Java library that allows remote attackers to obtain sensitive information through an "invalid curve attack" in elliptic curve Diffie Hellman key exchanges.
How does CVE-2015-7940 affect Bouncy Castle?
CVE-2015-7940 affects versions of the Bouncy Castle library before 1.51, where a point is not validated within the elliptic curve, making it easier for attackers to obtain private keys.
What is the severity of CVE-2015-7940?
CVE-2015-7940 has a severity rating of 5.3 (medium).
How can I fix CVE-2015-7940 in Bouncy Castle?
To fix CVE-2015-7940, update Bouncy Castle to version 1.51 or higher.
Where can I find more information about CVE-2015-7940?
You can find more information about CVE-2015-7940 at the following references: [CVE-2015-7940 on MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2015-7940), [Web-in-Security Blog](https://web-in-security.blogspot.ca/2015/09/practical-invalid-curve-attacks.html), [Ubuntu Security Notice USN-3727-1](https://ubuntu.com/security/notices/USN-3727-1).