CVE-2020-15164

Authentication Bypass in Scratch Login (mediawiki-scratch-login)

CRITICAL
10
CVSS Score
Published: August 28, 2020 at 05:05 PM UTC
Updated: June 17, 2026 at 02:56 AM UTC
2 products affected across 2 vendorsScratch LoginWiki Scratch Login

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Severity
CRITICAL10
Exploit prediction
EPSS 1%

Description

in Scratch Login (MediaWiki extension) before version 1.1, any account can be logged into by using the same username with leading, trailing, or repeated underscore(s), since those are treated as whitespace and trimmed by MediaWiki. This affects all users on any wiki using this extension. Since version 1.1, comments by users whose usernames would be trimmed on MediaWiki are ignored when searching for the verification code.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.1
Affected range stops below 1.1, so it looks safe — our inference, not a vendor statement
v < 1.1
Affected range stops below 1.1, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

10CRITICALGitHub_M
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
CHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-287CWE-74

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