Mix PHP: Deserialization of Untrusted Data
CVE-2026-37552 is a high-severity deserialization of untrusted data vulnerability in Mix PHP from Openmix, with a CVSS 3.1 base score of 8.4 out of 10. It can be exploited with local access to the system by an unauthenticated attacker, without any action from a user. Affected Mix PHP versions: 2.0.1 through 2.2.17. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.25% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Mix PHP you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.
How the severity score breaks down
- Attack vector
- LocalThe attacker needs local access or must trick a user into running something.
- 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:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (mitre.org).
Official description
Unsafe deserialization vulnerability in MixPHP Framework 2.x thru 2.2.17. The sync-invoke TCP server (Server.php:87) receives data from a TCP socket, passes it directly to Opis\Closure\unserialize(), then executes the result via call_user_func(). No authentication or signature verification exists on the TCP connection. An attacker with access to the localhost TCP port (server binds 127.0.0.1) can send a crafted serialized PHP closure to achieve arbitrary code execution.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Deserialization of Untrusted Data
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
How developers prevent this class of flaw
- If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
- When deserializing data, populate a new object rather than just deserializing. The result is that the data flows through safe input validation and that the functions are safe.
- Explicitly define a final object() to prevent deserialization.
More Deserialization of Untrusted Data vulnerabilities (CWE-502)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Third-party and government advisories
- gist.github.com/sgInnora/fa46386840fe978a30d7e53c458f2975Third Party Advisory
Other references
Recent Deserialization of Untrusted Data vulnerabilities
- 9.8 Critical severity
- 9.8 Critical severity
- 7.8 High severity
- 8.8 High severity
- 9.8 Critical severity
- 8.8 High severity
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