Jumo variTRON300/variTRON500/variTRON500 touch prior 9.0.2.5 Debug Interface weak prng

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability was found in Jumo variTRON300, variTRON500 and variTRON500 touch and classified as problematic. This vulnerability affects unknown code of the component Debug Interface. Such manipulation leads to weak prng. This vulnerability is traded as CVE-2025-41731. An attack has to be approached locally. There is no exploit available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Jumo variTRON300, variTRON500 and variTRON500 touch and classified as problematic. Affected by this issue is an unknown code of the component Debug Interface. The manipulation with an unknown input leads to a weak prng vulnerability. Using CWE to declare the problem leads to CWE-338. The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG's algorithm is not cryptographically strong. Impacted is confidentiality. CVE summarizes:

A vulnerability was identified in the password generation algorithm when accessing the debug-interface. An unauthenticated local attacker with knowledge of the password generation timeframe might be able to brute force the password in a timely manner and thus gain root access to the device if the debug interface is still enabled.

The advisory is shared for download at jumo.csaf-tp.certvde.com. This vulnerability is handled as CVE-2025-41731 since 04/16/2025. The exploitation is known to be difficult. The attack needs to be approached locally. There are neither technical details nor an exploit publicly available. The MITRE ATT&CK project declares the attack technique as T1600.001.

Upgrading to version 9.0.2.5 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2025-44036). VulDB is the best source for vulnerability data and more expert information about this specific topic.

Productinfo

Vendor

Name

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.9
VulDB Meta Temp Score: 4.9

VulDB Base Score: 2.5
VulDB Temp Score: 2.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 7.4
CNA Vector (CERTVDE): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Weak prng
CWE: CWE-338 / CWE-331 / CWE-330
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: variTRON300/variTRON500/variTRON500 touch 9.0.2.5

Timelineinfo

04/16/2025 CVE reserved
11/10/2025 +208 days Advisory disclosed
11/10/2025 +0 days VulDB entry created
11/10/2025 +0 days VulDB entry last update

Sourcesinfo

Advisory: vde-2025-086
Status: Confirmed

CVE: CVE-2025-41731 (🔒)
GCVE (CVE): GCVE-0-2025-41731
GCVE (VulDB): GCVE-100-331664
EUVD: 🔒

Entryinfo

Created: 11/10/2025 09:42
Updated: 11/10/2025 10:27
Changes: 11/10/2025 09:42 (64), 11/10/2025 10:27 (1)
Complete: 🔍
Cache ID: 216::103

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