CyberSecBulletin
CVE-2025-30095NVD status: Deferred

VyOS: Use of Hard-coded Cryptographic Key

Published Updated By the CyberSecBulletin desk

CVE-2025-30095 is a critical-severity use of hard-coded cryptographic key vulnerability in VyOS, with a CVSS 3.1 base score of 9.0 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists versions 1.4.2, 1.5-stream-2025-Q2 as the first without the flaw, so updating VyOS to one of those releases or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.5% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Update VyOS to 1.4.2 or 1.5-stream-2025-Q2, whichever matches your release line, 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
VyOSVyOSbefore 1.4.2; 1.5 up to, but not including, 1.5-stream-2025-Q21.4.2, 1.5-stream-2025-Q2

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
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
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:H/PR:N/UI:N/S:C/C:H/I:H/A:H. Scored by CNA (mitre.org).

Official description

VyOS 1.3 through 1.5 (fixed in 1.4.2) or any Debian-based system using dropbear in combination with live-build has the same Dropbear private host keys across different installations. Thus, an attacker can conduct active man-in-the-middle attacks against SSH connections if Dropbear is enabled as the SSH daemon. I n VyOS, this is not the default configuration for the system SSH daemon, but is for the console service. To mitigate this, one can run "rm -f /etc/dropbear/*key*" and/or "rm -f /etc/dropbear-initramfs/*key*" and then dropbearkey -t rsa -s 4096 -f /etc/dropbear_rsa_host_key and reload the service or reboot the system before using Dropbear as the SSH daemon (this clears out all keys mistakenly built into the release image) or update to the latest version of VyOS 1.4 or 1.5. Note that this vulnerability is not unique to VyOS and may appear in any Debian-based Linux distribution that uses Dropbear in combination with live-build, which has a safeguard against this behavior in OpenSSH but no equivalent one for Dropbear.

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

The underlying weakness: Use of Hard-coded Cryptographic Key

The product uses a hard-coded, unchangeable cryptographic key.

How developers prevent this class of flaw

  • Prevention schemes mirror that of hard-coded password storage.

More Use of Hard-coded Cryptographic Key vulnerabilities (CWE-321)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Use of Hard-coded Cryptographic Key vulnerabilities

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