Is CVE-2021-27786 actively exploited?

No active exploitation of CVE-2021-27786 has been confirmed so far. Continue monitoring, as exploit status can change.

Can CVE-2021-27786 be exploited remotely?

Yes. CVE-2021-27786 is exploitable remotely over the network (CVSS attack vector: Network).

What is the CVSS score of CVE-2021-27786?

CVE-2021-27786 has a CVSS score of 9.8 (CRITICAL).

HOME VULNERABILITIESCVE-2021-27786

CRITICAL

CVE-2021-27786

CWE-942Published: June 9, 2022· Updated: Jun 17, 2026

9.8

CVSS v3.1

Official Description

Cross-origin resource sharing (CORS) enables browsers to perform cross domain requests in a controlled manner. This request has an Origin header that identifies the domain that is making the initial request and defines the protocol between a browser and server to see if the request is allowed. An attacker can take advantage of this and possibly carry out privileged actions and access sensitive information when the Access-Control-Allow-Credentials is enabled.

NVD Source

Technical Analysis

CVE-2021-27786 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.