Shipo: Improper Authentication
CVE-2026-19907 is a critical-severity improper authentication vulnerability in Shipo, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Shipo versions: 1.6 through 1.8.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far, and no EPSS exploitation forecast has been published yet.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Shipo you run against the affected versions below, and install the vendor's latest release.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- NoneNo account or login is needed.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (wordfence.com).
Official description
The Shipo plugin for WordPress is vulnerable to Authentication Bypass in versions 1.6 through 1.8.0. This is due to the `authenticate_rest_user()` function parsing the `LOGGED_IN_COOKIE` value and authenticating the named user without verifying the cookie's cryptographic signature. The function's intended `/wp-json/shipo/` route restriction can also be bypassed by placing that substring in the query string of an unrelated REST endpoint. This makes it possible for unauthenticated attackers who know an existing username to impersonate that user, including an administrator, and perform authorized actions through the REST API, including creating another administrator account.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Authentication
When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct.
How developers prevent this class of flaw
- Use an authentication framework or library such as the OWASP ESAPI Authentication feature.
Timeline
- CVE record published.
References
Other references
Recent Improper Authentication vulnerabilities
- 8.1 High severity
- 8.3 High severity
- 7.5 High severity
- 8.1 High severity
- 8.7 High severity
- 7.5 High severity
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