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CVE-2016-9121: Go Jose Project: Inadequate Encryption Strength

CVE-2016-9121 is rated critical with a CVSS v3.0 base score of 9.1 and affects Go Jose Project. Per its scoring, it can be exploited over the network, without authentication, without any user interaction.

Vulnerability description

go-jose before 1.0.4 suffers from an invalid curve attack for the ECDH-ES algorithm. When deriving a shared key using ECDH-ES for an encrypted message, go-jose neglected to check that the received public key on a message is on the same curve as the static private key of the receiver, thus making it vulnerable to an invalid curve attack.

Severity breakdown

CVSS v3.0 9.1: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N

• Attack vector: Network. Exploitable remotely over the network, with no need for local or physical access.
• Attack complexity: Low. No special conditions; the attack can be repeated reliably.
• Privileges required: None. No account or prior access is needed.
• User interaction: None. No action from any user is needed.
• Scope: Unchanged. Impact stays within the vulnerable component.
• Confidentiality impact: High. Total loss of confidentiality; sensitive data can be fully disclosed.
• Integrity impact: High. Total loss of integrity; data or system state can be fully modified.
• Availability impact: None. No effect on availability.

Underlying weakness

CWE-326: Inadequate Encryption Strength

The product stores or transmits sensitive data using an encryption scheme that is theoretically sound, but is not strong enough for the level of protection required.

Affected products

• Go Jose Project: up to and including 1.0.3

References

• http://www.openwall.com/lists/oss-security/2016/11/03/1
• https://github.com/square/go-jose/commit/c7581939a3656bb65e89d64da0a52364a33d2507
• https://hackerone.com/reports/164590