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NOTICE UPDATED - April, 25th 2024

NIST has updated the NVD program announcement page with additional information regarding recent concerns and the temporary delays in enrichment efforts.

CVE-2021-21276 Detail

Description

Polr is an open source URL shortener. in Polr before version 2.3.0, a vulnerability in the setup process allows attackers to gain admin access to site instances, even if they do not possess an existing account. This vulnerability exists regardless of users' settings. If an attacker crafts a request with specific cookie headers to the /setup/finish endpoint, they may be able to obtain admin privileges on the instance. This is caused by a loose comparison (==) in SetupController that is susceptible to attack. The project has been patched to ensure that a strict comparison (===) is used to verify the setup key, and that /setup/finish verifies that no users table exists before performing any migrations or provisioning any new accounts. This is fixed in version 2.3.0. Users can patch this vulnerability without upgrading by adding abort(404) to the very first line of finishSetup in SetupController.php.


Severity



CVSS 4.0 Severity and Metrics:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.


NVD Analysts use publicly available information to associate vector strings and CVSS scores. We also display any CVSS information provided within the CVE List from the CNA.

Note: NVD Analysts have not published a CVSS score for this CVE at this time. NVD Analysts use publicly available information at the time of analysis to associate CVSS vector strings.

References to Advisories, Solutions, and Tools

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Hyperlink Resource
http://packetstormsecurity.com/files/171743/POLR-URL-2.3.0-Shortener-Admin-Takeover.html
https://github.com/cydrobolt/polr/commit/b1981709908caf6069b4a29dad3b6739c322c675 Patch  Third Party Advisory 
https://github.com/cydrobolt/polr/releases/tag/2.3.0 Release Notes  Third Party Advisory 
https://github.com/cydrobolt/polr/security/advisories/GHSA-vg6w-8w9v-xxqc Third Party Advisory 

Weakness Enumeration

CWE-ID CWE Name Source
NVD-CWE-Other Other cwe source acceptance level NIST  
CWE-863 Incorrect Authorization Contributor acceptance level GitHub, Inc.  

Known Affected Software Configurations Switch to CPE 2.2

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Change History

4 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2021-21276
NVD Published Date:
02/01/2021
NVD Last Modified:
04/06/2023
Source:
GitHub, Inc.