GHSA-4427-7f3w-mqv6 CVE-2020-12691 PYSEC-2020-55

OpenStack Keystone V3 /credentials endpoint policy logic allows to change credentials owner or target project ID

High PyPI

Severity: 0.0 / 10; High · CVSS 4.0
Exploit chance (EPSS): 4.92%; Chance of exploitation in the next 30 days. Higher than 92.12% of scored vulnerabilities.
Known exploited: No; Not in CISA's catalog
Weakness: CWE-311 Missing Encryption of Sensitive Data; CWE-863 Incorrect Authorization
Fix: 15.0.1; Upgrade keystone to this version or later

Description

An issue was discovered in OpenStack Keystone before 15.0.1, and 16.0.0. Any authenticated user can create an EC2 credential for themselves for a project that they have a specified role on, and then perform an update to the credential user and project, allowing them to masquerade as another user. This potentially allows a malicious user to act as the admin on a project another user has the admin role on, which can effectively grant that user global admin privileges.

Affected versions

PyPI

Package	Vulnerable	Fixed in
keystone	`< 15.0.1`	`15.0.1`
keystone	`>= 16.0.0, < 16.0.1`	`16.0.1`

How to fix

Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.

keystone PyPI → `15.0.1`

pip

pip install --upgrade "keystone>=15.0.1"

poetry

poetry add "keystone>=15.0.1"

uv

uv add "keystone>=15.0.1"

Severity breakdown

CVSS 4.0 0.0

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

Attack vector: Network
Attack complexity: Low
Attack requirements: None
Privileges required: Low
User interaction: None
Confidentiality (vulnerable system): High
Integrity (vulnerable system): High
Availability (vulnerable system): High
Confidentiality (subsequent systems): None
Integrity (subsequent systems): None
Availability (subsequent systems): None

CVSS 3.1 8.8

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Attack vector: Network
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: High
Availability: High

Weakness

CWE-311: Missing Encryption of Sensitive Data

The product does not encrypt sensitive or critical information before storage or transmission.

How to prevent it

Requirements: Clearly specify which data or resources are valuable enough that they should be protected by encryption. Require that any transmission or storage of this data/resource should use well-vetted encryption algorithms.
Architecture and Design: Ensure that encryption is properly integrated into the system design, including but not necessarily limited to: Encryption that is needed to store or transmit private data of the users of the system Encryption that is needed to protect the system itself from unauthorized disclosure or tampering Identify the separate needs and contexts for encryption: One-way (i.e., only the user or recipient needs to have the key). This can be achieved using public key cryptography, or other techniques in which the encrypting party (i.e., the product) does not need to have access to a private key. Two-way (i.e., the encryption can be automatically performed on behalf of a user, but the key must be available so that the plaintext can be automatically recoverable by that user). This requires storage of the private key in a format that is recoverable only by the user (or perhaps by the operating system) in a way that cannot be recovered by others. Using threat modeling or other techniques, assume that data can be compromised through a separate vulnerability or weakness, and determine where encryption will be most effective. Ensure that data that should be private is not being inadvertently exposed using weaknesses such as insecure permissions (CWE-732). [REF-7]
Architecture and Design: When there is a need to store or transmit sensitive data, use strong, up-to-date cryptographic algorithms to encrypt that data. Select a well-vetted algorithm that is currently considered to be strong by experts in the field, and use well-tested implementations. As with all cryptographic mechanisms, the source code should be available for analysis. For example, US government systems require FIPS 140-2 certification. Do not develop custom or private cryptographic algorithms. They will likely be exposed to attacks that are well-understood by cryptographers. Reverse engineering techniques are mature. If the algorithm can be compromised if attackers find out how it works, then it is especially weak. Periodically ensure that the cryptography has not become obsolete. Some older algorithms, once thought to require a billion years of computing time, can now be broken in days or hours. This includes MD4, MD5, SHA1, DES, and other algorithms that were once regarded as strong. [REF-267]
Architecture and Design: Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area. Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
Implementation, Architecture and Design: When using industry-approved techniques, use them correctly. Don't cut corners by skipping resource-intensive steps (CWE-325). These steps are often essential for preventing common attacks.
Implementation: Use naming conventions and strong types to make it easier to spot when sensitive data is being used. When creating structures, objects, or other complex entities, separate the sensitive and non-sensitive data as much as possible.

CWE-863: Incorrect Authorization

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.

How to prevent it

Architecture and Design: 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.
Architecture and Design: Ensure that access control checks are performed related to the business logic. These checks may be different than the access control checks that are applied to more generic resources such as files, connections, processes, memory, and database records. For example, a database may restrict access for medical records to a specific database user, but each record might only be intended to be accessible to the patient and the patient's doctor [REF-7].
Architecture and Design: 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].
Architecture and Design: 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.
System Configuration, Installation: Use the access control capabilities of your operating system and server environment and define your access control lists accordingly. Use a "default deny" policy when defining these ACLs.

References

Advisories

Packages

github.com/openstack/keystone

Timeline

May 7, 2020 Published
Jun 10, 2026 Last updated by the source
Oct 31, 2026 Latest EPSS score

Advisory	Severity	Why it's related
GHSA-whqr-fgm5-x77q OpenStack Keystone's federated token rescoping mechanism doesn't propagate the original token's expiry to the newly issued token	High	Also affects keystone
GHSA-q623-f4j4-p4xj OpenStack Keystone has an Incorrect Authorization issue	High	Also affects keystone
GHSA-2r23-2g6v-2m5f OpenStack Keystone has an Authorization Bypass	High	Also affects keystone
GHSA-8f8m-wrvr-wcvf OpenStack Keystone doesn't verify that the user supplied in the authentication request matches the owner of the application credential	High	Also affects keystone
GHSA-hhq2-3832-xxcv OpenStack Keystone has an Incorrect Authorization Issue	High	Also affects keystone
GHSA-pfx2-9x9m-7ghx OpenStack Keystone: LDAP identity backend does not convert enabled attribute to boolean	High	Also affects keystone
GHSA-4phw-6824-6cfp OpenStack Keystone: Restricted application credentials can create EC2 credentials	Medium	Also affects keystone
GHSA-hcqg-5g63-7j9h OpenStack Keystone allows /v3/ec2tokens or /v3/s3tokens request with valid AWS Signature to provide Keystone authorization.	High	Also affects keystone

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