CVE-2021-29504 Information

Description

WP-CLI is the command-line interface for WordPress. An improper error handling in HTTPS requests management in WP-CLI version 0.12.0 and later allows remote attackers able to intercept the communication to remotely disable the certificate verification on WP-CLI side gaining full control over the communication content including the ability to impersonate update servers and push malicious updates towards WordPress instances controlled by the vulnerable WP-CLI agent or push malicious updates toward WP-CLI itself. The vulnerability stems from the fact that the default behavior of WP_CLI\Utils\http_request() when encountering a TLS handshake error is to disable certificate validation and retry the same request. The default behavior has been changed with version 2.5.0 of WP-CLI and the wp-cli/wp-cli framework (via https://github.com/wp-cli/wp-cli/pull/5523) so that the WP_CLI\Utils\http_request() method accepts an $insecure option that is false by default and consequently that a TLS handshake failure is a hard error by default. This new default is a breaking change and ripples through to all consumers of WP_CLI\Utils\http_request() including those in separate WP-CLI bundled or third-party packages. https://github.com/wp-cli/wp-cli/pull/5523 has also added an --insecure flag to the cli update command to counter this breaking change. There is no direct workaround for the default insecure behavior of wp-cli/wp-cli versions before 2.5.0. The workaround for dealing with the breaking change in the commands directly affected by the new secure default behavior is to add the --insecure flag to manually opt-in to the previous insecure behavior.

CVSS Vector

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Reference

https://github.com/wp-cli/config-command/pull/128 https://github.com/wp-cli/core-command/pull/186 https://github.com/wp-cli/wp-cli/pull/5523 https://github.com/wp-cli/package-command/pull/138 https://github.com/wp-cli/extension-command/pull/287 https://github.com/wp-cli/checksum-command/pull/86 https://github.com/wp-cli/wp-cli/security/advisories/GHSA-rwgm-f83r-v3qj

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction Required

NONE

Scope

NONE

Confidentiality Impact

UNCHANGED

Integrity Impact

HIGH

Availability Impact

HIGH

Base Score

NONE

Base Severity

7.4