CVE-2026-95806 MISP: PHP phar stream wrapper enables deserialization and code execution via caller-influenced filesystem paths
Attackers can achieve arbitrary code execution by exploiting the PHP phar stream wrapper to trigger deserialization via manipulated filesystem paths.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-95806?
CVE-2026-95806 is a high-severity unsafe deserialization vulnerability in MISP, published on 22 Sep 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
MISP ships with PHP's phar stream wrapper registered in both its web entry point and its console entry point.
The phar stream wrapper causes PHP to treat a phar archive as a directory, which has two security consequences:
- any filesystem operation on a caller-influenced path that resolves to a phar archive triggers an implicit unserialize() call, creating a deserialization sink; - a relocated application root can reach executable code inside an uploaded phar file, enabling arbitrary code execution as the web user.
No component of MISP, the vendored CakePHP framework, or any runtime-loaded library reads or constructs phar archives. The wrapper therefore serves no legitimate purpose in the MISP runtime and exists solely as an available primitive for an attacker who can influence a filesystem path argument.
Which versions are affected by CVE-2026-95806?
How do I fix CVE-2026-95806?
No fix has been published for CVE-2026-95806 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-2026-95806 being exploited?
There is no known exploitation of CVE-2026-95806 in the wild and no public exploit code.
Sources
Also known as GHSA-8rgx-3gvf-26gg.