CVE-2020-15237

Timing attack in Shrine

State: Published
Severity: 5.9 Medium
Published: Oct 5, 2020
Updated: Aug 4, 2024
Reserved: Jun 25, 2020

Description

In Shrine before version 3.3.0, when using the `derivation_endpoint` plugin, it'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.

Scores

CVSS	Score	Vector	Source
3.1	5.9 Medium	CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N	GitHub_M

Weaknesses

CWE-208 {"CWE-208":"Observable Timing Discrepancy"}
CWE-203 {"CWE-203":"Observable Differences in Behavior to Error Inputs"}

Affected Products

Product	Versions
shrineshrinerb	< 3.3.0Affected

References

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