CVE-2021-21276

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Summary

CVECVE-2021-21276
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-02-01 15:15:00 UTC
Updated2023-04-06 17:15:00 UTC
DescriptionPolr 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.

Risk And Classification

Problem Types: CWE-863

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Application Polrproject Polr All All All All
Application Polrproject Polr All All All All

References

ReferenceSourceLinkTags
Privilege escalation vulnerability in setup process · Advisory · cydrobolt/polr · GitHub CONFIRM github.com Third Party Advisory
POLR URL 2.3.0 Shortener Admin Takeover ≈ Packet Storm MISC packetstormsecurity.com
Release 2.3.0 · cydrobolt/polr · GitHub MISC github.com Release Notes, Third Party Advisory
Merge pull request from GHSA-vg6w-8w9v-xxqc · cydrobolt/polr@b198170 · GitHub MISC github.com Patch, Third Party Advisory
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

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