CVE-2020-15237

Severity CVSS v4.0:

Pending analysis

Type:

Unavailable / Other

Publication date:

05/10/2020

Last modified:

19/10/2020

Description

In Shrine before version 3.3.0, when using the `derivation_endpoint` plugin, it&#39;s possible for the attacker to use a timing attack to guess the signature of the derivation URL. The problem has been fixed by comparing sent and calculated signature in constant time, using `Rack::Utils.secure_compare`. Users using the `derivation_endpoint` plugin are urged to upgrade to Shrine 3.3.0 or greater. A possible workaround is provided in the linked advisory.

Impact

Vector 3.x

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N CVSS v3.1 Severity and Metrics:

Base Score: 5.90 MEDIUM
Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): High
Privileges Required (PR): None
User Interaction (UI): None
Scope (S): Unchanged
Confidentiality (C): High
Integrity (I): None
Availability (A): None

Base Score 3.x

5.90

Severity 3.x

MEDIUM

Vector 2.0

AV:N/AC:M/Au:N/C:P/I:N/A:N CVSS v2.0 Severity and Metrics:

Base Score: 4.30 MEDIUM
Vector: AV:N/AC:M/Au:N/C:P/I:N/A:N

Attack Vector (AV): Network
Attack Complexity (AC): Medium
Authentication (Au): None
Confidentiality (C): Physical
Integrity (I): None
Availability (A): None