CVE-2025-41696VulnerabilityPublished 9 Dec 2025

CVE-2025-41696: Phoenix Contact FL SWITCH 2005 · Use of Hard-coded Credentials

Affects Phoenix Contact FL SWITCH 2005Source CVE Database V5

Mentioned vulnerabilities

CVE-2025-41692

Not known to be exploited · CVSS 4.6 Medium.

Data as of 26 Oct 2026, 06:26 UTC

CVSS 3.1 base score

4.6Medium

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

EPSS: 0.2% chance of exploitation in 30 days – higher than 11% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.

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

Attack Vector: Physical
Attack Complexity: Low
Privileges Required: None
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: Physical: The attack requires the attacker to physically touch or manipulate the vulnerable component. Physical interaction may be brief or persistent.
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
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 9 Dec 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 2026-10-25.

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 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
Phoenix Contact FL SWITCH 2005	Affected =0.0.0	Fixed in–

AI-suggested

1. Physically secure all Phoenix Contact FL SWITCH 2005 devices to prevent unauthorized access to the UART port, including locking network cabinets and restricting access to authorized personnel only. 2. Implement strict access control and monitoring around industrial network equipment to detect and respond to any physical tampering attempts. 3. Use network segmentation to isolate vulnerable devices from critical network segments, limiting the impact of any compromise. 4. Monitor device logs and network traffic for unusual read or configuration access patterns that may indicate exploitation attempts. 5. Engage with Phoenix Contact for updates and patches addressing this vulnerability and plan timely deployment once available. 6. Consider replacing or upgrading devices with known hardcoded credential issues if patching is not feasible in the short term. 7. Conduct regular security audits and penetration tests focusing on physical security and embedded device vulnerabilities. 8. Educate operational technology (OT) staff about the risks of undocumented hardware interfaces and hardcoded credentials to improve detection and prevention.

Description

An attacker can use an undocumented UART port on the PCB as a side-channel with the user hardcoded credentials obtained from CVE-2025-41692 to gain read access to parts of the filesystem of the device.

Impact

For European organizations, especially those operating critical infrastructure, manufacturing, or industrial automation environments, this vulnerability poses a risk of sensitive information disclosure. Attackers gaining read access to the filesystem could extract configuration data, network credentials, or other sensitive operational information, potentially facilitating further attacks or espionage. While the vulnerability does not directly impact system integrity or availability, the confidentiality breach could undermine trust in network security and lead to targeted attacks. The requirement for physical access limits the threat to environments where devices are not adequately secured against unauthorized personnel. However, in industrial settings where devices may be deployed in less physically secure locations, the risk increases. The exposure of hardcoded credentials could also enable lateral movement within the network if attackers combine this vulnerability with others. European organizations must consider the potential for industrial espionage, sabotage, or compliance violations due to unauthorized data access.

CWE-798Use of Hard-coded Credentials (opens in a new tab)
Base weaknessLikelihood of exploit: HighOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product contains hard-coded credentials, such as a password or cryptographic key.
Architecture and Design
For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. Properly protect the key (CWE-320).
Architecture and Design
For inbound authentication: Rather than hard-code a default username and password, key, or other authentication credentials for first time logins, utilize a "first login" mode that requires the user to enter a unique strong password or key.
Architecture and Design
If the product must contain hard-coded credentials or they cannot be removed, perform access control checks and limit which entities can access the feature that requires the hard-coded credentials. For example, a feature might only be enabled through the system console instead of through a network connection.
OWASP Cheat Sheets
Key Management (opens in a new tab)
REST Security (opens in a new tab)
JSON Web Token for Java (opens in a new tab)
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V2.10.4 (opens in a new tab)
V6.4.1 (opens in a new tab)
V3.5.2 (opens in a new tab)
Attack patterns
Read Sensitive Constants Within an Executable (opens in a new tab)
Try Common or Default Usernames and Passwords (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

certvde.com/de/advisories/VDE-2025-071 (opens in a new tab)

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 16 Dec 2025, 10:35 UTC

WeaknessesCWE-798

Technical details

References

Community reviews

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