CyberSecBulletin
CVE-2025-34393NVD status: Analyzed

RMM: Use of Externally-Controlled Input to Select Classes or Code

CVE-2025-34393 is a critical-severity use of externally-controlled input to select classes or code vulnerability in RMM from Barracuda Networks, with a CVSS 3.1 base score of 9.8 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 2025.1.1 as the first without the flaw, so updating RMM to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.76% chance of exploitation within 30 days, higher than 56% of scored CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update RMM to 2025.1.1 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Barracuda NetworksRMM2025.1 up to, but not including, 2025.1.12025.1.1

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
LowNo special conditions are needed; the attack works reliably.
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:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.010.0CriticalCNA (vulncheck.com)
CVSS 3.19.8CriticalNVD

Official description

Barracuda Service Center, as implemented in the RMM solution, in versions prior to 2025.1.1, does not correctly verify the name of an attacker-controlled WSDL service, leading to insecure reflection. This can result in remote code execution through either invocation of arbitrary methods or deserialization of untrusted types.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Use of Externally-Controlled Input to Select Classes or Code

The product uses external input with reflection to select which classes or code to use, but it does not sufficiently prevent the input from selecting improper classes or code.

How developers prevent this class of flaw

  • Refactor your code to avoid using reflection.
  • Do not use user-controlled inputs to select and load classes or code.
  • Apply strict input validation by using allowlists or indirect selection to ensure that the user is only selecting allowable classes or code.

More Use of Externally-Controlled Input to Select Classes or Code vulnerabilities (CWE-470)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in RMM

All RMM vulnerabilities

Recent Use of Externally-Controlled Input to Select Classes or Code vulnerabilities

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