Pfsense: Deserialization of Untrusted Data
CVE-2025-69690 is a critical-severity deserialization of untrusted data vulnerability in Pfsense, with a CVSS 3.1 base score of 9.1 out of 10. It can be exploited remotely over the network by an attacker with administrator privileges, without any action from a user. Affected Pfsense versions: 2.7.2. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.81% chance of exploitation within 30 days, higher than 57% of scored CVEs.
Critical severity: a successful attack would have severe impact.
What to do
- Check which version of Pfsense 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
- NetworkCan be exploited remotely over a network, including the internet.
- Attack complexity
- LowNo special conditions are needed; the attack works reliably.
- Privileges required
- HighAdministrator-level access is required first.
- User interaction
- NoneNo action by a victim is required.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- 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:L/PR:H/UI:N/S:C/C:H/I:H/A:H. Scored by CISA (ADP).
Official description
Netgate pfSense CE 2.7.2 allows code execution by using the module installer with a backup file with a serialized PHP object containing the post_reboot_commands property. NOTE: the Supplier disputes this because this installer is only available to admins and they are intentionally allowed to execute PHP code.
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: poc, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Technical write-ups (may include proof of concept)
- seclists.org/fulldisclosure/2026/Feb/16Exploit, Mailing List, Third Party Advisory
Other references
- linkedin.com/in/nelson-adhepeau/Not Applicable
Other vulnerabilities in Pfsense
- 8.8 High severity
- 7.2 High severity
- 7.2 High severity
- 7.2 High severity
- 7.2 High severity
- 7.2 High severity
Recent Deserialization of Untrusted Data vulnerabilities
- 9.2 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 9.8 Critical severity
- 8.1 High severity
- 8.4 High severity
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