CVE-2021-20868

Incorrect authorization vulnerability in KONICA MINOLTA bizhub series (bizhub C750i G00-35 and earlier, bizhub C650i/C550i/C450i G00-B6 and earlier, bizhub C360i/C300i/C250i G00-B6 and earlier, bizhub 750i/650i/550i/450i G00-37 and earlier, bizhub 360i/300i G00-33 and earlier, bizhub C287i/C257i/C227i G00-19 and earlier, bizhub 306i/266i/246i/226i G00-B6 and earlier, bizhub C759/C659 GC7-X8 and earlier, bizhub C658/C558/C458 GC7-X8 and earlier, bizhub 958/808/758 GC7-X8 and earlier, bizhub 658e/558e/458e GC7-X8 and earlier, bizhub C287/C227 GC7-X8 and earlier, bizhub 287/227 GC7-X8 and earlier, bizhub 368e/308e GC7-X8 and earlier, bizhub C368/C308/C258 GC9-X4 and earlier, bizhub 558/458/368/308 GC9-X4 and earlier, bizhub C754e/C654e GDQ-M0 and earlier, bizhub 754e/654e GDQ-M0 and earlier, bizhub C554e/C454e GDQ-M1 and earlier, bizhub C364e/C284e/C224e GDQ-M1 and earlier, bizhub 554e/454e/364e/284e/224e GDQ-M1 and earlier, bizhub C754/C654 C554/C454 GR1-M0 and earlier, bizhub C364/C284/C224 GR1-M0 and earlier, bizhub 754/654 GR1-M0 and earlier, bizhub C4050i/C3350i/C4000i/C3300i G00-B6 and earlier, bizhub C3320i G00-B6 and earlier, bizhub 4750i/4050i G00-22 and earlier, bizhub 4700i G00-22 and earlier, bizhub C3851FS/C3851/C3351 GC9-X4 and earlier, and bizhub 4752/4052 GC9-X4 and earlier) allows an attacker on the adjacent network to obtain user credentials if external server authentication is enabled via a specific SOAP message sent by an administrative user.

Weakness

The product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. This allows attackers to bypass intended access restrictions.

Affected Software

Extended Description

Assuming a user with a given identity, authorization is the process of determining whether that user can access a given resource, based on the user’s privileges and any permissions or other access-control specifications that apply to the resource. When access control checks are incorrectly applied, users are able to access data or perform actions that they should not be allowed to perform. This can lead to a wide range of problems, including information exposures, denial of service, and arbitrary code execution.

Potential Mitigations

• Divide the product into anonymous, normal, privileged, and administrative areas. Reduce the attack surface by carefully mapping roles with data and functionality. Use role-based access control (RBAC) [REF-229] to enforce the roles at the appropriate boundaries.
• Note that this approach may not protect against horizontal authorization, i.e., it will not protect a user from attacking others with the same role.
• Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
• For example, consider using authorization frameworks such as the JAAS Authorization Framework [REF-233] and the OWASP ESAPI Access Control feature [REF-45].
• For web applications, make sure that the access control mechanism is enforced correctly at the server side on every page. Users should not be able to access any unauthorized functionality or information by simply requesting direct access to that page.
• One way to do this is to ensure that all pages containing sensitive information are not cached, and that all such pages restrict access to requests that are accompanied by an active and authenticated session token associated with a user who has the required permissions to access that page.

References

• https://jvn.jp/en/vu/JVNVU95192472/index.html
• https://jvn.jp/vu/JVNVU95192472/index.html
• https://www.konicaminolta.com/global/newsroom/topics/2021/1224-01-01.html
• https://www.konicaminolta.jp/business/support/important/211224_01_01.html