5.4
MEDIUM CVSS 3.1
CVE-2026-56309
Capgo - Plan Bypass via Unrestricted Attachment Upload Endpoint
Description

Capgo before 12.128.2 fails to enforce plan/quota restrictions on the /files/upload/attachments endpoint, allowing plan-blocked apps to create publicly readable R2 objects. Attackers can upload arbitrary attachments using upload-scoped API keys that bypass plan checks, persist outside normal bundle metadata, and survive app deletion, enabling storage and bandwidth abuse.

INFO

Published Date :

July 10, 2026, 3:16 p.m.

Last Modified :

July 10, 2026, 4:16 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-56309 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 3.1 MEDIUM [email protected]
CVSS 4.0 MEDIUM 83251b91-4cc7-4094-a5c7-464a1b83ea10
CVSS 4.0 MEDIUM [email protected]
Solution
Update Capgo to a version that enforces plan/quota restrictions on file uploads.
  • Update Capgo to version 12.128.2 or later.
  • Verify API key permissions and plan restrictions.
  • Review and secure the /files/upload/attachments endpoint.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-56309.

URL Resource
https://github.com/Cap-go/capgo/security/advisories/GHSA-q52j-ggvx-cr4v
https://www.vulncheck.com/advisories/capgo-plan-bypass-via-unrestricted-attachment-upload-endpoint
https://github.com/Cap-go/capgo/security/advisories/GHSA-q52j-ggvx-cr4v
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-56309 is associated with the following CWEs:

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-56309 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-56309 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0

    Jul. 10, 2026

    Action Type Old Value New Value
    Added Reference https://github.com/Cap-go/capgo/security/advisories/GHSA-q52j-ggvx-cr4v
    Added SSVC {'id': 'CVE-2026-56309', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'poc'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-10T15:12:45.415501Z'}
  • New CVE Received by [email protected]

    Jul. 10, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'Capgo', 'product': 'Capgo', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '12.128.2', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '12.128.2', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}]
    Added Description Capgo before 12.128.2 fails to enforce plan/quota restrictions on the /files/upload/attachments endpoint, allowing plan-blocked apps to create publicly readable R2 objects. Attackers can upload arbitrary attachments using upload-scoped API keys that bypass plan checks, persist outside normal bundle metadata, and survive app deletion, enabling storage and bandwidth abuse.
    Added CVSS V4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
    Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
    Added CWE CWE-770
    Added Reference https://github.com/Cap-go/capgo/security/advisories/GHSA-q52j-ggvx-cr4v
    Added Reference https://www.vulncheck.com/advisories/capgo-plan-bypass-via-unrestricted-attachment-upload-endpoint
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.