CyberSecBulletin
CVE-2026-56239NVD status: Deferred

Capgo: Improper Privilege Management

CVE-2026-56239 is a high-severity improper privilege management vulnerability in Capgo, with a CVSS 3.1 base score of 7.6 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. The record lists version 12.128.2 as the first without the flaw, so updating Capgo to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.35% 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. Update Capgo to 12.128.2 or a later version.
  2. Read the advisory on github.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
CapgoCapgobefore 12.128.212.128.2

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
LowPerformance or availability is reduced.

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

Scoring systemScoreSeverityScored by
CVSS 4.07.2HighCNA (vulncheck.com)
CVSS 3.17.6HighCNA (vulncheck.com)

Official description

Capgo before 12.128.2 contains a potential privilege escalation vulnerability in the public.apply_usage_overage SECURITY DEFINER function, which performs sensitive billing operations without enforcing internal authorization checks (no validation of auth.uid(), org membership, or check_min_rights). Because the function runs with the owner's privileges, it bypasses Row Level Security. If EXECUTE permission is available to the authenticated or anon roles (explicitly or via default privileges), an authenticated user could invoke it via Supabase RPC to manipulate billing data for arbitrary organizations, including unauthorized credit depletion and fraudulent overage event insertion.

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

The underlying weakness: Improper Privilege Management

The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor.

How developers prevent this class of flaw

  • Very carefully manage the setting, management, and handling of privileges. Explicitly manage trust zones in the software.
  • Follow the principle of least privilege when assigning access rights to entities in a software system.
  • Consider following the principle of separation of privilege. Require multiple conditions to be met before permitting access to a system resource.

More Improper Privilege Management vulnerabilities (CWE-269)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Capgo

All Capgo vulnerabilities

Recent Improper Privilege Management vulnerabilities

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