Vulnerability CVE-2021-30159

Vulnerability Name:

CVE-2021-30159 (CCN-199719)

Assigned:

2021-01-19

Published:

2021-01-19

Updated:

2022-05-27

Summary:

An issue was discovered in MediaWiki before 1.31.12 and 1.32.x through 1.35.x before 1.35.2. Users can bypass intended restrictions on deleting pages in certain "fast double move" situations. MovePage::isValidMoveTarget() uses FOR UPDATE, but it's only called if Title::getArticleID() returns non-zero with no special flags. Next, MovePage::moveToInternal() will delete the page if getArticleID(READ_LATEST) is non-zero. Therefore, if the page is missing in the replica DB, isValidMove() will return true, and then moveToInternal() will unconditionally delete the page if it can be found in the master.

CVSS v3 Severity:

4.3 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N)
3.8 Low (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:U/RL:O/RC:C)

Exploitability Metrics:	Attack Vector (AV): Network Attack Complexity (AC): Low Privileges Required (PR): Low User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): None Integrity (I): Low Availibility (A): None

6.5 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L)
5.7 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L/E:U/RL:O/RC:C)

Exploitability Metrics:	Attack Vector (AV): Network Attack Complexity (AC): Low Privileges Required (PR): None User Interaction (UI): None
Scope:	Scope (S): Unchanged
Impact Metrics:	Confidentiality (C): None Integrity (I): Low Availibility (A): Low

CVSS v2 Severity:

4.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:S/C:N/I:P/A:N)

Exploitability Metrics:	Access Vector (AV): Network Access Complexity (AC): Low Authentication (Au): Single_Instance
Impact Metrics:	Confidentiality (C): None Integrity (I): Partial Availibility (A): None

6.4 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:P/A:P)

Exploitability Metrics:	Access Vector (AV): Network Access Complexity (AC): Low Athentication (Au): None
Impact Metrics:	Confidentiality (C): None Integrity (I): Partial Availibility (A): Partial