CVE-2026-16267 Newsletters < 4.16 - Unauthenticated PHP Object Injection via Date Form Field
Unauthenticated attackers can inject arbitrary PHP objects via the date form field in the Newsletters plugin, potentially leading to code execution.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-16267?
CVE-2026-16267 is a high-severity unsafe deserialization vulnerability in Unknown Newsletters, published on 8 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
The Newsletters WordPress plugin before 4.16 does not restrict the classes allowed when unserialising a value taken from a public form submission, allowing unauthenticated attackers to inject arbitrary PHP objects.
Weakness: CWE-502
Which versions are affected by CVE-2026-16267?
How do I fix CVE-2026-16267?
No fix has been published for CVE-2026-16267 yet. Limit exposure of the affected software until one is available.
Upgrade, and only deserialise data from trusted sources or with an allow-list of types. More about Unsafe deserialization.
Is CVE-2026-16267 being exploited?
There is no known exploitation of CVE-2026-16267 in the wild and no public exploit code.
Sources
Also known as GHSA-jxc3-pfg8-hv86.