Virtualizor: Deserialization of Untrusted Data
CVE-2026-43642 is a high-severity deserialization of untrusted data vulnerability in Virtualizor from Softaculous, with a CVSS 3.1 base score of 8.1 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 3.2.9 (Patch 9) as the first without the flaw, so updating Virtualizor to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.96% chance of exploitation within 30 days, higher than 62% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update Virtualizor to 3.2.9 (Patch 9) or a later version.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Softaculous | Virtualizor | before 3.2.9 (Patch 9) | 3.2.9 (Patch 9) |
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
- HighSuccess depends on conditions outside the attacker's control.
- 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:H/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).
| Scoring system | Score | Severity | Scored by |
|---|---|---|---|
| CVSS 4.0 | 9.2 | Critical | CNA (vulncheck.com) |
| CVSS 3.1 | 8.1 | High | CNA (vulncheck.com) |
Official description
Softaculous Virtualizor before 3.2.9 (Patch 9) and 3.0.0 contains a PHP object injection vulnerability in the billing module handler that allows unauthenticated remote attackers to supply arbitrary serialized PHP objects for deserialization by setting the act parameter to login with the from_billing_module parameter present. Attackers can pass malicious serialized data through the billing_data POST field to the unserialize() function without allowed_classes restrictions, enabling exploitation of available POP chains to achieve remote code execution as root.
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
Other references
Other vulnerabilities in Virtualizor
- 7.5 High severity
- 9.8 Critical severity
Recent Deserialization of Untrusted Data vulnerabilities
- 9.8 Critical severity
- 8.8 High severity
- 8.8 High severity
- 7.7 High severity
- 9.8 Critical severity
- 8.8 High severity
Spotted an error? Tell us.