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CVE-2026-112305NVD status: Deferred

Semaphore UI: Improperly Controlled Modification of Dynamically-Determined Object Attributes

CVE-2026-112305 is a high-severity improperly controlled modification of dynamically-determined object attributes vulnerability in Semaphore UI from Semaphoreui, with a CVSS 3.1 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Semaphore UI versions: 2.19.16 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.56% 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 Semaphore UI you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
SemaphoreuiSemaphore UI2.19.16 and earlierNot 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
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
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:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.08.7HighCNA (vulncheck.com)
CVSS 3.18.8HighCNA (vulncheck.com)

Official description

Semaphore UI through 2.19.16 contains a remote code execution vulnerability that allows users with the task_runner role to override protected Ansible variables by supplying arbitrary keys in the task environment JSON. Attackers can POST tasks setting ansible_ssh_common_args with a ProxyCommand or ansible_connection=local to execute commands as the Semaphore server user, exposing encryption keys, SSH keys and stored secrets.

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

The underlying weakness: Improperly Controlled Modification of Dynamically-Determined Object Attributes

The product receives input from an upstream component that specifies multiple attributes, properties, or fields that are to be initialized or updated in an object, but it does not properly control which attributes can be modified.

How developers prevent this class of flaw

  • If available, use features of the language or framework that allow specification of allowlists of attributes or fields that are allowed to be modified. If possible, prefer allowlists over denylists. For applications written with Ruby on Rails, use the attr_accessible (allowlist) or attr_protected (denylist) macros in each class that may be used in mass assignment.
  • If available, use the signing/sealing features of the programming language to assure that deserialized data has not been tainted. For example, a hash-based message authentication code (HMAC) could be used to ensure that data has not been modified.
  • For any externally-influenced input, check the input against an allowlist of internal object attributes or fields that are allowed to be modified.

More Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerabilities (CWE-915)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).

References

Recent Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerabilities

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