CyberSecBulletin
CVE-2026-54160NVD status: Awaiting Analysis

nut: Inclusion of Functionality from Untrusted Control Sphere

Published Updated By the CyberSecBulletin desk

CVE-2026-54160 is a high-severity inclusion of functionality from untrusted control sphere vulnerability in nut from Networkupstools, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. Affected nut versions: < 658b24ef8410648ceca6d5a59e8690efbc8c36bc. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Check which version of nut you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  4. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
Networkupstoolsnut< 658b24ef8410648ceca6d5a59e8690efbc8c36bcNot stated

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
RequiredA user must take an action such as opening a file or link.
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
LowPerformance or availability is reduced.

Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:H/I:H/A:L. Scored by CNA (github.com).

Official description

Network UPS Tools is a collection of programs which provide a common interface for monitoring and administering UPS, PDU and SCD hardware. Prior to commits 658b24e and 1aa31d1, the GitHub Actions script used to prepare NUT tarballs and update GitHub Checks statuses and PR comments about it was mis-structured in terms of mixing code running with higher privileges (single-use token generated with write permissions) and untrusted inputs (PR source branch). A malicious PR run from a fork could extract the GITHUB_TOKEN value. It could potentially be abused while it was valid (while the GHA job ran) to manipulate Git repository contents, commit checks/statuses, or issue/PR comments, according to permissions it was issued with. This issue has been patched via commits 658b24e and 1aa31d1.

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

The underlying weakness: Inclusion of Functionality from Untrusted Control Sphere

The product imports, requires, or includes executable functionality (such as a library) from a source that is outside of the intended control sphere.

How developers prevent this class of flaw

  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.
  • When the set of acceptable objects, such as filenames or URLs, is limited or known, create a mapping from a set of fixed input values (such as numeric IDs) to the actual filenames or URLs, and reject all other inputs. For example, ID 1 could map to inbox.txt and ID 2 could map to profile.txt. Features such as the ESAPI AccessReferenceMap provide this capability.
  • For any security checks that are performed on the client side, ensure that these checks are duplicated on the server side, in order to avoid CWE-602. Attackers can bypass the client-side checks by modifying values after the checks have been performed, or by changing the client to remove the client-side checks entirely. Then, these modified values would be submitted to the server.

More Inclusion of Functionality from Untrusted Control Sphere vulnerabilities (CWE-829)

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

Other vulnerabilities in nut

All nut vulnerabilities

Recent Inclusion of Functionality from Untrusted Control Sphere vulnerabilities

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