CyberSecBulletin
CVE-2026-108740NVD status: Deferred

GoatCounter: Improperly Controlled Modification of Dynamically-Determined Object Attributes

Published Updated By the CyberSecBulletin desk

CVE-2026-108740 is a high-severity improperly controlled modification of dynamically-determined object attributes vulnerability in GoatCounter from Arp242, with a CVSS 3.1 base score of 8.3 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 GoatCounter versions: 2.7.0 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 0.33% 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 GoatCounter you run against the affected versions below, and install the vendor's latest release.

Affected products and versions

VendorProductAffected versionsFixed in
Arp242GoatCounter2.7.0 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
LowSome restricted data 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:L/I:H/A:H. Scored by CNA (vulncheck.com).

Scoring systemScoreSeverityScored by
CVSS 4.07.2HighCNA (vulncheck.com)
CVSS 3.18.3HighCNA (vulncheck.com)

Official description

GoatCounter through 2.7.0 contains a mass assignment privilege escalation vulnerability in the userPrefSave handler that allows logged-in users to modify protected account fields via form-encoded requests. Attackers with read-only access can POST user.access[all]=* and user.email_verified=true to /user/pref, bypassing readonly tags to gain superuser or admin access.

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).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Improperly Controlled Modification of Dynamically-Determined Object Attributes vulnerabilities

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