SecuriTricks - CVE-2025-14546

Description

Versions of the package fastapi-sso before 0.19.0 are vulnerable to Cross-site Request Forgery (CSRF) due to the improper validation of the OAuth state parameter during the authentication callback. While the get_login_url method allows for state generation, it does not persist the state or bind it to the user's session. Consequently, the verify_and_process method accepts the state received in the query parameters without verifying it against a trusted local value. This allows a remote attacker to trick a victim into visiting a malicious callback URL, which can result in the attacker's account being linked to the victim's internal account.

Product(s) Impacted

Product	Versions

Weaknesses

Common security weaknesses mapped to this vulnerability.

CWE-285

Improper Authorization

The product does not perform or incorrectly performs an authorization check when an actor attempts to access a resource or perform an action.

References

https://github.com/tomasvotava/fastapi-sso/commit/6117d1a5ad498ba57d671e8a059ebe20db5abe02

https://github.com/tomasvotava/fastapi-sso/issues/266

https://security.snyk.io/vuln/SNYK-PYTHON-FASTAPISSO-14386403

CVSS Score

6.9 / 10

CVSS Data - 4.0

Attack Vector: NETWORK
Attack Complexity: LOW
Attack Requirements: NONE
Privileges Required: LOW
User Interaction: ACTIVE
Scope:
Confidentiality Impact: HIGH
Integrity Impact: LOW
Availability Impact: NONE
Exploit Maturity: PROOF_OF_CONCEPT

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:A/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:P/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

View Vector String

Timeline

Published: Dec. 19, 2025, 5:16 a.m.
Last Modified: Dec. 19, 2025, 6 p.m.

Status : Awaiting Analysis

CVE has been marked for Analysis. Normally once in this state the CVE will be analyzed by NVD staff within 24 hours.

More info

Source

report@snyk.io

CVE-2025-14546