CVE-2020-26236 Detail

Description

In ScratchVerifier before commit a603769, an attacker can hijack the verification process to log into someone else's account on any site that uses ScratchVerifier for logins. A possible exploitation would follow these steps: 1. User starts login process. 2. Attacker attempts login for user, and is given the same verification code. 3. User comments code as part of their normal login. 4. Before user can, attacker completes the login process now that the code is commented. 5. User gets a failed login and attacker now has control of the account. Since commit a603769 starting a login twice will generate different verification codes, causing both user and attacker login to fail. For clients that rely on a clone of ScratchVerifier not hosted by the developers, their users may attempt to finish the login process as soon as possible after commenting the code. There is no reliable way for the attacker to know before the user can finish the process that the user has commented the code, so this vulnerability only really affects those who comment the code and then take several seconds before finishing the login.


Severity



CVSS 3.x Severity and Metrics:

NIST CVSS score
NIST: NVD
Base Score:  N/A
NVD score not yet provided.

Nist CVSS score does not match with CNA score
CNA:  GitHub, Inc.
Base Score:  7.5 HIGH
Vector:  CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: NVD Analysts have not published a CVSS score for this CVE at this time. NVD Analysts use publicly available information at the time of analysis to associate CVSS vector strings. A CNA provided score within the CVE List has been displayed.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
https://github.com/ScratchVerifier/ScratchVerifier/commit/a603769010abf8c1bede91af46e4945314e4aa4a
https://github.com/ScratchVerifier/ScratchVerifier/security/advisories/GHSA-99cr-hvf7-85g9

Weakness Enumeration

CWE-ID CWE Name Source
CWE-287 Improper Authentication Provider acceptance level GitHub, Inc.  

Change History

0 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2020-26236
NVD Published Date:
11/20/2020
NVD Last Modified:
11/20/2020
Source:
GitHub, Inc.