CVE-2026-56309

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.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	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

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-10 15:16

Updated : 2026-07-10 16:16

NVD link : CVE-2026-56309

Mitre link : CVE-2026-56309

CVE.ORG link : CVE-2026-56309

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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