Newsletters < 4.16 - Unauthenticated API Authentication Bypass via Type Juggling
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · Low · Low
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-287.
Summary
The Newsletters WordPress plugin before 4.16 does not strictly compare its API authentication key, allowing unauthenticated attackers to bypass the API authentication via type juggling and perform privileged actions such as modifying subscriber records and sending emails, when the optional API has been enabled.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Unknown | Newsletters | before 4.16 | 4.16 | Patch available | CNA |
- Newsletters VendorUnknown Affected before 4.16 Fixed in 4.16 Patch available CNA
Remediation
- Fix · CNA Newsletters (Unknown) Fixed in 4.16
Fixed in the same release
Records fixed by the same vendor advisory or release, as the CNA lists them.
- Release ·
Newsletters 4.16
2 records Highest priority Priority LOW 2 LOW
Other records, highest priority first
- TI-2026-13602 Newsletters < 4.16 - Unauthenticated PHP Object Injection via Date Form FieldPriority LOW 38
Timeline
- 2026-10-02 Threatist record created from CVE-2026-16269
- 2026-10-03 Alias added: GHSA-5mfh-c59g-8688
References
Sources
- CVE-2026-16269 · CVE Program
- CVE-2026-16269 · NVD
- FIRST EPSS
- GHSA-5mfh-c59g-8688 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences