Vulnerability · Published Jun 7, 2021 · Assigned by GitHub_M
CVE-2021-29504Improper Certificate Validation in WP-CLI framework
Critical 9.1
In plain English
A critical-severity improper certificate validation in wp-cli from wp-cli. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 1.3% (higher than 71% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official 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.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Packagist | wp-cli/wp-cli | 2.5.0 | GHSA-rwgm-f83r-v3qj |
Affected products (as reported)
Weakness: CWE-295 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
References
- https://github.com/wp-cli/wp-cli/security/advisories/GHSA-rwgm-f83r-v3qj x_refsource_CONFIRM
- https://github.com/wp-cli/checksum-command/pull/86 x_refsource_MISC
- https://github.com/wp-cli/config-command/pull/128 x_refsource_MISC
- https://github.com/wp-cli/core-command/pull/186 x_refsource_MISC
- https://github.com/wp-cli/extension-command/pull/287 x_refsource_MISC
- https://github.com/wp-cli/package-command/pull/138 x_refsource_MISC
- https://github.com/wp-cli/wp-cli/pull/5523 x_refsource_MISC