CVE-2020-12607

An issue was discovered in fastecdsa before 2.1.2. When using the NIST P-256 curve in the ECDSA implementation, the point at infinity is mishandled. This means that for an extreme value in k and s^-1, the signature verification fails even if the signature is correct. This behavior is not solely a usability problem. There are some threat models where an attacker can benefit by successfully guessing users for whom signature verification will fail.

CVSS v3.0 7.5 HIGH
CVSS v2.0 5.0 MEDIUM

7.5^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

5.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:N/AC:L/Au:N/C:P/I:N/A:N

Exploitability : 10.0 / Impact : 2.9

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact NONE

Availability Impact NONE

References

Link	Resource
https://github.com/AntonKueltz/fastecdsa/commit/4a16daeaf139be20654ef58a9fe4c79dc030458c	Issue Tracking Patch Third Party Advisory
https://github.com/AntonKueltz/fastecdsa/commit/7b64e3efaa806b4daaf73bb5172af3581812f8de	Patch Third Party Advisory
https://github.com/AntonKueltz/fastecdsa/issues/52	Exploit Third Party Advisory
https://github.com/AntonKueltz/fastecdsa/commit/e592f106edd5acf6dacedfab2ad16fe6c735c9d1	Patch Third Party Advisory

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Configurations

Configuration 1 (hide)

cpe:2.3:a:fastecdsa_project:fastecdsa:*:*:*:*:*:*:*:*

Information

Published : 2020-06-02 14:15

Updated : 2020-06-03 06:47

NVD link : CVE-2020-12607

Mitre link : CVE-2020-12607

JSON object : View

CWE

CWE-347

Improper Verification of Cryptographic Signature

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Products Affected

fastecdsa_project

fastecdsa

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