CVE-2020-13927

Apache Airflow's Experimental API: Authentication Bypass

As of , CVE-2020-13927 in Apache Airflow's Experimental API is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 18 January 2022
US federal deadline
18 July 2022181 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Not known to CISA
EPSS score
0.99Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
Not availableCISA listed it before 4 February 2022, where the EPSS files we read begin.
Public exploit
1 Metasploit module and 1 Exploit-DB entry
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

The previous default setting for Airflow's Experimental API was to allow all API requests without authentication.

CISA's description

The previous default setting for Airflow's Experimental API was to allow all API requests without authentication, but this poses security risks to users who miss this fact. From Airflow 1.10.11 the default has been changed to deny all requests by default and is documented at https://airflow.apache.org/docs/1.10.11/security.html#api-authentication. Note this change fixes it for new installs but existing users need to change their config to default `[api]auth_backend = airflow.api.auth.backend.deny_all` as mentioned in the Updating Guide: https://github.com/apache/airflow/blob/1.10.11/UPDATING.md#experimental-api-will-deny-all-request-by-default

The CVE record's description, from apache

CVE published
10 November 2020
Assigned by
apache
CVSS
9.8 Critical (CVSS 3.1, from CISA-ADP)
CWE-306
Missing Authentication for Critical Function
CWE-1188
Initialization of a Resource with an Insecure Default
CWE-1056
Invokable Control Element with Variadic Parameters
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. Exploit-DB published an exploit (EDB-ID 49927).
  3. CISA added it to its list of exploited vulnerabilities.
  4. The US federal deadline to fix it.

Public exploits

Facts from Metasploit's module list and Exploit-DB's index; we never copy exploit code.

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