CVE-2026-56329

Capgo before 12.128.2 contains a cross-tenant preview namespace collision vulnerability caused by non-bijective decoding of double underscores to dots in preview hostname parsing. Attackers can register app IDs with underscores that collide with other tenants' dotted app IDs, causing preview misrouting and denial of preview access for victim applications.

CVSS v3 6.4 MEDIUM

6.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.1 / Impact : 2.7

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope CHANGED

References

Link	Resource
https://github.com/Cap-go/capgo/security/advisories/GHSA-76qq-gg2p-pwwj
https://www.vulncheck.com/advisories/capgo-cross-tenant-preview-namespace-collision-via-non-bijective-underscore-decoding
https://github.com/Cap-go/capgo/security/advisories/GHSA-76qq-gg2p-pwwj

Configurations

No configuration.

History

10 Jul 2026, 17:17

Type	Values Removed	Values Added
References	~~() https://github.com/Cap-go/capgo/security/advisories/GHSA-76qq-gg2p-pwwj -~~	() https://github.com/Cap-go/capgo/security/advisories/GHSA-76qq-gg2p-pwwj -

10 Jul 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-10 15:16

Updated : 2026-07-10 17:17

NVD link : CVE-2026-56329

Mitre link : CVE-2026-56329

CVE.ORG link : CVE-2026-56329

JSON object : View

Products Affected

No product.

CWE

CWE-436

Interpretation Conflict

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