VulnerabilityPublished 2 Sep 2025

CVE-2025-9260: Fluent Forms (WordPress plugin) · Deserialization of Untrusted Data

Affects Fluent Forms (WordPress plugin)Source CVE Database V5

Not known to be exploited · CVSS 6.5 Medium · fixed in 6.1.2 : update Fluent Forms (WordPress plugin) when convenient.

Data as of 26 Oct 2026, 12:55 UTC

CVSS 3.1 base score

6.5Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.5% chance of exploitation in 30 days – higher than 47% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 6.1.2

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Attack Vector: Network
Attack Complexity: Low
Privileges Required: Low
User Interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: None

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: Low: The attacker is authorized with (i.e., requires) privileges that provide basic user capabilities that could normally affect only settings and files owned by a user. Alternatively, an attacker with Low privileges may have the ability to cause an impact only to non-sensitive resources.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: High: There is total loss of confidentiality, resulting in all resources within the impacted component being divulged to the attacker. Alternatively, access to only some restricted information is obtained, but the disclosed information presents a direct, serious impact.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 2 Sep 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Affected software

Product	Affected	Fixed in
techjewel Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder	Affected =5.1.16	Fixed in–

AI-suggested

Organizations should immediately verify the version of Fluent Forms installed on their WordPress sites and upgrade to version 6.1.2 or later, which contains the complete and stable patch for this vulnerability. If upgrading is not immediately possible, restrict access to the WordPress admin and subscriber-level accounts through strong authentication mechanisms and monitor for unusual activity. Disable the PHP allow_url_include directive if it is enabled, as this setting significantly increases the risk of remote code execution. Implement web application firewalls (WAFs) with rules targeting PHP Object Injection patterns and monitor logs for suspicious deserialization attempts. Conduct regular security audits of WordPress plugins and configurations to detect outdated or vulnerable components. Educate administrators about the risks of granting unnecessary privileges to users and enforce the principle of least privilege. Finally, maintain backups and incident response plans to quickly recover from potential exploitation.

Description

The Fluent Forms – Customizable Contact Forms, Survey, Quiz, & Conversational Form Builder plugin for WordPress is vulnerable to PHP Object Injection in versions 5.1.16 to 6.1.1 via deserialization of untrusted input in the parseUserProperties function. This makes it possible for authenticated attackers, with Subscriber-level access and above, to inject a PHP Object. The additional presence of a POP chain allows attackers to read arbitrary files. If allow_url_include is enabled on the server, remote code execution is possible. While the vendor patched this issue in version 6.1.0, the patch caused a fatal error in the vulnerable code, due to a missing class import, so we consider 6.1.2 to be the most complete and best patched version

Impact

This vulnerability poses a moderate risk to organizations using the affected Fluent Forms plugin versions. Attackers with low-level authenticated access can exploit it to read arbitrary files, potentially exposing sensitive data such as configuration files, credentials, or personal user information. In environments where allow_url_include is enabled—a misconfiguration but still present in some legacy or poorly managed servers—attackers can escalate this to remote code execution, leading to full server compromise. This can result in data breaches, defacement, malware deployment, or lateral movement within the network. Since WordPress is widely used globally, and Fluent Forms is a popular plugin, many websites could be affected, including corporate, governmental, and e-commerce platforms. The requirement for authenticated access limits exposure somewhat, but given that Subscriber roles are common, the attack surface remains broad. The incomplete initial patch increased risk temporarily, as some sites may have upgraded to 6.1.0 expecting a fix but remained vulnerable or unstable. Overall, the vulnerability can undermine confidentiality and potentially availability if exploited in certain configurations, impacting organizational reputation, compliance, and operational continuity.

CWE-502Deserialization of Untrusted Data (opens in a new tab)
Base weaknessLikelihood of exploit: MediumCWE Top 25 (2025): #15OWASP Top 10 A08:2025: Software or Data Integrity Failures (opens in a new tab)
The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.
Architecture and Design · Implementation
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.
Implementation
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.
Implementation
Explicitly define a final object() to prevent deserialization.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
Deserialization (opens in a new tab)
XML Security (opens in a new tab)
XML External Entity Prevention (opens in a new tab)
Software Supply Chain Security (opens in a new tab)
OWASP ASVS 4.0.3
V1.5.2 (opens in a new tab)
V5.5.3 (opens in a new tab)
V5.5.1 (opens in a new tab)
Attack patterns
Object Injection (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 26 Feb 2026, 17:49 UTC

WeaknessesCWE-502

Technical details

References

Community reviews

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